P-glycoprotein Inhibition Increases the Brain Distribution and Antidepressant-Like Activity of Escitalopram in Rodents

PubMed Central

O'Brien, Fionn E; O'Connor, Richard M; Clarke, Gerard; Dinan, Timothy G; Griffin, Brendan T; Cryan, John F

2013-01-01

Despite the clinical prevalence of the antidepressant escitalopram, over 30% of escitalopram-treated patients fail to respond to treatment. Recent gene association studies have highlighted a potential link between the drug efflux transporter P-glycoprotein (P-gp) and response to escitalopram. The present studies investigated pharmacokinetic and pharmacodynamic interactions between P-gp and escitalopram. In vitro bidirectional transport studies revealed that escitalopram is a transported substrate of human P-gp. Microdialysis-based pharmacokinetic studies demonstrated that administration of the P-gp inhibitor cyclosporin A resulted in increased brain levels of escitalopram without altering plasma escitalopram levels in the rat, thereby showing that P-gp restricts escitalopram transport across the blood–brain barrier (BBB) in vivo. The tail suspension test (TST) was carried out to elucidate the pharmacodynamic impact of P-gp inhibition on escitalopram effect in a mouse model of antidepressant activity. Pre-treatment with the P-gp inhibitor verapamil enhanced the response to escitalopram in the TST. Taken together, these data indicate that P-gp may restrict the BBB transport of escitalopram in humans, potentially resulting in subtherapeutic brain concentrations in certain patients. Moreover, by verifying that increasing escitalopram delivery to the brain by P-gp inhibition results in enhanced antidepressant-like activity, we suggest that adjunctive treatment with a P-gp inhibitor may represent a beneficial approach to augment escitalopram therapy in depression. PMID:23670590

Longitudinal Numbers-Needed-To-Treat (NNT) for Achieving Various Levels of Analgesic Response and Improvement with Etoricoxib, Naproxen, and Placebo in Ankylosing Spondylitis

PubMed Central

2011-01-01

Background Clinical analgesic trials typically report response as group mean results. However, research has shown that few patients are average and most have responses at the extremes. Moreover, group mean results do not convey response levels and thus have limited value in representing the benefit-risk at an individual level. Responder analyses and numbers-needed-to-treat (NNT) are considered more relevant for evaluating treatment response. We evaluated levels of analgesic response and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score improvement and the associated NNTs. Methods This was a post-hoc analysis of a 6-week, randomized, double-blind study (N = 387) comparing etoricoxib 90 mg, etoricoxib 120 mg, naproxen 1000 mg, and placebo in AS. Spine pain and BASDAI were measured on a 100-mm visual analog scale. The number and percentage of patients achieving ≥30% and ≥50% improvement in both BASDAI and spine pain were calculated and used to determine the corresponding NNTs. Patients who discontinued from the study for any reason were assigned zero improvement beyond 7 days of the time of discontinuation. Results For etoricoxib 90 mg, etoricoxib 120 mg and naproxen 1000 mg, the NNTs at 6 weeks compared with placebo were 2.0, 2.0, and 2.7 respectively for BASDAI ≥30% improvement, and 3.2, 2.8, and 4.1 for ≥50% improvement. For spine pain, the NNTs were 1.9, 2.0, and 3.2, respectively, for ≥30% improvement, and 2.7, 2.5, and 3.7 for ≥50% improvement. The differences between etoricoxib and naproxen exceeded the limit of ±0.5 units described as a clinically meaningful difference for pain. Response rates and NNTs were generally similar and stable over 2, 4, and 6 weeks. Conclusions For every 2 patients treated with etoricoxib, 1 achieved a clinically meaningful (≥30%) improvement in spine pain and BASDAI beyond that expected from placebo, whereas the corresponding values were approximately 1 in every 3 patients treated with naproxen. Use of NNTs and responder analyses provide additional, complementary information beyond population mean responses when assessing efficacy compared to placebo and amongst active therapies. PMID:21767407

Is there any analgesic benefit from preoperative vs. postoperative administration of etoricoxib in total knee arthroplasty under spinal anaesthesia?: A randomised double-blind placebo-controlled trial.

PubMed

Munteanu, Ana Maria; Cionac Florescu, Simona; Anastase, Denisa Madalina; Stoica, Cristian Ioan

2016-11-01

Optimal postoperative analgesia is a challenge for the anaesthesiologist, with the ideal combination of methods, drugs, doses and timing of administration still the subject of research. The COX-2 inhibitors are a class of NSAIDs that may provide useful perioperative analgesia but the optimal timing of administration has not been elucidated. We hypothesised that etoricoxib given 1 h before total knee arthroplasty under spinal anaesthesia will decrease the cumulative dose of intravenous and subcutaneous morphine required to maintain pain intensity of 3 or less on a 10-point numerical rating scale (NRS) during the first postoperative 48 h compared with the same dose of etoricoxib given after surgery. Randomised, double-blind, placebo-controlled trial. University hospital, between January and September, 2014. Overall, 165 patients scheduled for total knee arthroplasty under spinal anaesthesia. The patients were randomised into one of three groups: the ETORICOX-PREOP group received etoricoxib 120 mg orally 1 h before surgery, one placebo pill at the end of surgery and a further 120 mg etoricoxib after 24 h; the ETORICOX-POSTOP group received one placebo pill 1 h before surgery and etoricoxib 120 mg at the end of surgery and after 24 h. The PLACEBO group received one placebo pill 1 h before surgery, one at end of surgery and a third after 24 h. The primary outcome measure was the cumulative dose of intravenous and subcutaneous morphine required during the first postoperative 48 h to maintain a 10-point numerical pain rating scale value of 3 or less. Secondary outcomes measures were duration of analgesia from initiation of spinal anaesthesia until the first analgesic requirement and the side-effects of the treatment. The quantity of morphine over the first postoperative 48 h required by the ETORICOX-PREOP group (44 ± 16 mg) and the ETORICOX-POSTOP group (52 ± 23 mg) were both significantly less than the PLACEBO group (71 ± 20 mg) (P = 0.001), demonstrating a morphine-sparing effect of etoricoxib of the order of 30%; the difference between the PRE vs. POST groups was statistically significant (P = 0.02), favouring a preemptive analgesic effect. Also, there was evidence of a longer time to first analgesia compared with PLACEBO in the PREOP group (P = 0.02) but no significant difference between PREOP and POSTOP groups (P = 0.30). There was no difference in side-effects among the three study groups and there were no serious adverse effects of etoricoxib. Preemptive administration of etoricoxib 120 mg orally in patients undergoing total knee arthroplasty under spinal anaesthesia is superior to postoperative administration of the same dose in terms of its morphine-sparing effect during the first postoperative 48 h, but not in prolonging the time to first analgesia, and is associated with a similar incidence of side-effects. Clinicaltrials.gov identifier: NCT 02534610.

Comparing etoricoxib and celecoxib for preemptive analgesia for acute postoperative pain in patients undergoing arthroscopic anterior cruciate ligament reconstruction: a randomized controlled trial

PubMed Central

2010-01-01

Background The efficacy of selective cox-2 inhibitors in postoperative pain reduction were usually compared with conventional non-selective conventional NSAIDs or other types of medicine. Previous studies also used selective cox-2 inhibitors as single postoperative dose, in continued mode, or in combination with other modalities. The purpose of this study was to compare analgesic efficacy of single preoperative administration of etoricoxib versus celecoxib for post-operative pain relief after arthroscopic anterior cruciate ligament reconstruction. Methods One hundred and two patients diagnosed as anterior cruciate ligament injury were randomized into 3 groups using opaque envelope. Both patients and surgeon were blinded to the allocation. All of the patients were operated by one orthopaedic surgeon under regional anesthesia. Each group was given either etoricoxib 120 mg., celecoxib 400 mg., or placebo 1 hour prior to operative incision. Post-operative pain intensity, time to first dose of analgesic requirement and numbers of analgesic used for pain control and adverse events were recorded periodically to 48 hours after surgery. We analyzed the data according to intention to treat principle. Results Among 102 patients, 35 were in etoricoxib, 35 in celecoxib and 32 in placebo group. The mean age of the patients was 30 years and most of the injury came from sports injury. There were no significant differences in all demographic characteristics among groups. The etoricoxib group had significantly less pain intensity than the other two groups at recovery room and up to 8 hours period but no significance difference in all other evaluation point, while celecoxib showed no significantly difference from placebo at any time points. The time to first dose of analgesic medication, amount of analgesic used, patient's satisfaction with pain control and incidence of adverse events were also no significantly difference among three groups. Conclusions Etoricoxib is more effective than celecoxib and placebo for using as preemptive analgesia for acute postoperative pain control in patients underwent arthroscopic anterior cruciate ligament reconstruction. Trial registration number NCT01017380 PMID:20973952

Efficacy of escitalopram in the treatment of social anxiety disorder: A meta-analysis versus placebo.

PubMed

Baldwin, David S; Asakura, Satoshi; Koyama, Tsukasa; Hayano, Taiji; Hagino, Atsushi; Reines, Elin; Larsen, Klaus

2016-06-01

Escitalopram is the most selective of the serotonin reuptake inhibitor (SSRI) antidepressants. We conducted a meta-analysis of placebo-controlled studies where escitalopram was used to treat patients with social anxiety disorder (SAD). Data from all randomised, double-blind placebo-controlled studies in SAD with escitalopram from both specialist settings and general practice were used. Patients met the DSM-IV criteria for SAD, were ≥18 years old, and had a Liebowitz Social Anxiety Scale (LSAS) ≥60. The primary outcome measure was the estimated treatment difference in LSAS total score at Week 12. Secondary outcome measures included the estimated treatment difference in the Clinical Global Impression-Severity (CGI-S) score at Week 12. A total of 1598 patients from 3 randomised controlled trials were included in the analyses. Escitalopram (n=1061) was superior to placebo (n=537), with an estimated treatment difference on the LSAS of -9.2 points (95%CI: [-14.4; -4.0], p<0.01) (escitalopram 5mg/day), -4.6 points (95%CI: [-8.1; -1.0], p<0.01) (escitalopram 10mg/day), -10.1 points (95%CI: [-13.7; -6.5], p<0.01) (escitalopram 20mg/day) and -7.3 points (95%CI: [-12.3; -2.2], p<0.01) (escitalopram 10-20mg/day). For the CGI-S, the corresponding values were -0.55 points (95%CI: [-0.79; -0.31], p<0.01) (escitalopram 5mg/day), -0.26 points (95%CI: [-0.42; -0.10], p<0.01) (escitalopram 10mg/day), -0.48 points (95%CI: [-0.64; -0.31], p<0.01) (escitalopram 20mg/day) and -0.29 points (95%CI: [-0.51; -0.07], p<0.05) (escitalopram 10-20mg/day). The withdrawal rate due to adverse events was 7.2% for escitalopram, compared with 4.3% for placebo (p<0.05). In this meta-analysis, all doses of escitalopram showed significant superiority in efficacy versus placebo in the treatment of patients with SAD. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

Sensitivity of single-domain versus multiple-domain outcome measures to identify responders in chronic low-back pain: pooled analysis of 2 placebo-controlled trials of etoricoxib.

PubMed

Jensen, Mark P; Schnitzer, Thomas J; Wang, Hongwei; Smugar, Steven S; Peloso, Paul M; Gammaitoni, Arnold

2012-01-01

A composite responder index for chronic low-back pain (CLBP) has recently been proposed to evaluate the efficacy of CLBP treatments in clinical trials. We compared the responsiveness of this composite measure with a number of single-item responder definitions. We pooled data from 2 placebo-controlled studies of etoricoxib in CLBP to evaluate 5 response criteria: 30% pain intensity (PI) reduction; 50% PI reduction; 20 mm absolute reduction (100 mm PI visual analog scale); patient global assessment of response to therapy (PGART); and the composite criteria of 30% reduction in PI+30% improvement in PGART of disease status+no worsening in function. We used bootstrap analysis and logistic regression to assess the ability to differentiate etoricoxib and placebo, and the κ coefficient to assess agreement among the responder criteria. The criterion of a 20 mm improvement in PI resulted in the greatest proportion (71.5%) of patients being classified as responders and all criteria separated etoricoxib from placebo (P≤0.0001). PGART had the highest discriminant ability (odds ratio 5.90), and was significantly (P<0.05) more discriminant than the 20 mm and ≥30% improvements and the composite criteria. After adjusting for all other measures, only PGART continued to show a significant treatment effect for etoricoxib versus placebo (P=0.0003). Kappa values contrasting the composite criteria and the single-item measures ranged from 0.59 to 0.85. These findings do not support the superiority of a composite index over single-item ratings of PI and PGART ratings, but do suggest that PGART ratings may be more responsive to treatment, perhaps because they measure something in addition to change in PI.

Cost-effectiveness of escitalopram vs. citalopram in major depressive disorder.

PubMed

Fantino, Bruno; Moore, Nicholas; Verdoux, Hélène; Auray, Jean-Paul

2007-03-01

Clinical trials have shown better efficacy of escitalopram over citalopram, and review-based economic models the cost-effectiveness of escitalopram vs. citalopram (brand and generic). No head-to-head clinical trial has, however, evaluated the cost-effectiveness of both drugs so far. The aim of this study was to assess the relative cost-effectiveness of escitalopram compared with citalopram in patients with major depressive disorder. An economic evaluation was conducted alongside a double-blind randomized clinical trial conducted by general practitioners and psychiatrists comparing fixed doses of escitalopram (20 mg/day) or citalopram (40 mg/day) over 8 weeks in ambulatory care patients with major depressive disorder (baseline Montgomery-Asberg Depression Rating Scale score > or =30). Resources use was recorded using a standardized form recording use of healthcare services and days of sick leave for the 2-month prestudy period and for the 8-week study period. Statistically significant improvements were observed in patients treated with escitalopram. Mean per-patient costs for the escitalopram group, compared with the citalopram group, were 41% lower (96 euro vs. 163 euro; P<0.05) from a healthcare perspective. Differences were mostly related to lower hospitalization costs for escitalopram compared with citalopram recipients, assuming a parity price between escitalopram and citalopram. Bootstrapped distributions of the cost-effectiveness ratios also showed better effectiveness and lower costs for escitalopram compared with citalopram. Escitalopram is significantly more effective than citalopram, and is associated with lower healthcare costs. This prospective economic analysis demonstrated that escitalopram is a cost-effective first-line treatment option for major depressive disorder.

Comparison of toxicity of acute overdoses with citalopram and escitalopram.

PubMed

Hayes, Bryan D; Klein-Schwartz, Wendy; Clark, Richard F; Muller, Allison A; Miloradovich, Jane E

2010-07-01

Seizures and QTc prolongation are associated with citalopram poisoning; however, overdose experience with escitalopram is more limited. The goals of this study were to compare citalopram's vs. escitalopram's clinical effects in overdose, including the incidence of seizures. A retrospective review was conducted for single-substance acute overdoses with citalopram and escitalopram, managed in hospitals, that were reported to six U.S. poison centers from 2002-2005. There were 374 citalopram and 421 escitalopram overdose cases. Gender and ages were similar between the two, with 68-70% females and a median age of 20 years for citalopram and 18 years for escitalopram. Median dose by history was 310 mg for citalopram and 130 mg for escitalopram. More serious outcomes were associated with citalopram overdoses (p < 0.001). Most frequently reported clinical effects with citalopram and escitalopram were tachycardia, drowsiness, hypertension, and vomiting. Seizures (30 vs. 1, respectively, p < 0.001) and tremor (32 vs. 13, respectively, p = 0.001) were more common with citalopram. QTc prolongation occurred in 14 citalopram cases and 7 escitalopram cases (p = 0.109). There was an association between increasing dose and severity of outcome for citalopram (p < 0.001) and escitalopram (p = 0.011). In children < 6 years old, 12 of 66 citalopram and 5 of 57 escitalopram cases experienced toxicity, such as drowsiness, nausea/vomiting, and tachycardia. There were no seizures in this age group. Escitalopram seems to be less toxic than citalopram after an acute overdose; seizures and tremors were more common with citalopram. Initial management of overdoses should include seizure precautions for citalopram and cardiac monitoring for both drugs. Copyright 2010 Elsevier Inc. All rights reserved.

Clinical pharmacology review of escitalopram for the treatment of depression.

PubMed

Pastoor, Devin; Gobburu, Joga

2014-01-01

Depression is a serious and debilitating psychiatric condition with serious societal health and economic implications. Escitalopram , the S-enantiomer of racemic citalopram, is an effective treatment for major depressive disorder. This review covers the clinical pharmacology of escitalopram, with emphasis on regulatory approval. Its pharmacokinetics, pharmacodynamics and clinical efficacy for major depressive disorder are evaluated, along with data regarding safety and tolerability. Drug development of escitalopram was heavily guided by prior approval of citalopram. Select safety and efficacy studies for escitalopram in combination with supportive evidence from the results of prior citalopram studies allowed for regulatory approval for acute and maintenance claims in both adults and adolescents, while minimizing burden on the sponsor. Escitalopram has been shown to have better efficacy and safety profile than other selective serotonin reuptake inhibitor and serotonin norepinephrine reuptake inhibitor drugs, including racemic citalopram. The first generic escitalopram was approved in 2012, along with Abbreviated New Drug Applications. The associated cost savings have helped reduce the burden of weighing the benefits of escitalopram over less-expensive alternatives.

A review of escitalopram and citalopram in child and adolescent depression.

PubMed

Carandang, Carlo; Jabbal, Rekha; Macbride, Angela; Elbe, Dean

2011-11-01

To review the basic pharmacology and published literature regarding escitalopram and citalopram in child and adolescent depression. A LITERATURE REVIEW WAS CONDUCTED USING THE SEARCH TERMS: 'escitalopram', 'citalopram', 'depression', 'randomized controlled trial', 'open label trial' and limits set to: Human trials, English Language and All Child (Age 0-18). Additional articles were identified from reference information and poster presentation data. Three prospective, randomized controlled trials (RCT) were found for escitalopram in pediatric depression, and two RCTs were found for citalopram. One RCT each for escitalopram and citalopram showed superiority over placebo on the primary out come measure. Adverse effects in escitalopram and citalopram trials were generally mild to moderate. Suicidality was not assessed systematically in all RCTs reviewed, but did not appear to be elevated over placebo in escitalopram RCTs. One trial reported numerically higher suicide related events for citalopram compared to placebo (14 vs. 5, p=0.06). At present, escitalopram and citalopram should be considered a second-line option for adolescent depression. The US Food and Drug Administration approval of escitalopram for treatment of adolescent depression was based on a single positive RCT. This is less evidence than typically required for approval of a drug for a new indication.

Density functional theory studies of etoricoxib

NASA Astrophysics Data System (ADS)

Sachdeva, Ritika; Kaur, Prabhjot; Singh, V. P.; Saini, G. S. S.

2016-05-01

Etoricoxib is a COX-2 selective inhibitor drug with molecular formula C18H15ClN2O2S. It is primarily used for the treatment of arthritis(rheumatoid, psoriatic, osteoarthritis), ankylosing spondylitis, gout and chronic low back pain. Theoretical studies of the molecule including geometry optimization and vibrational frequency calculations were carried out with the help of density functional theory calculations using 6-311++ g (d, p) basis set and B3LYP functional.

A question about the potential cardiac toxicity of escitalopram.

PubMed

Howland, Robert H

2012-04-01

Previous reviews have focused on the potential cardiac toxicity of the racemic drug citalopram (Celexa(®)). Evaluating the safety of escitalopram (Lexapro(®)) is an important issue to consider, since it is the S-enantiomer of citalopram. Escitalopram has a small effect on the QTc interval. A prolonged QTc was seen in 2% to 14% of escitalopram overdose cases, without serious cardiac sequelae. The QTc prolongation effect of citalopram in beagle dogs has been attributed to the minor metabolite racemic didemethylcitalopram (DDCT). Whether the escitalopram minor metabolite S-DDCT has this effect is not known. Concentrations of S-DDCT are lower than DDCT, but for a broad range of doses of escitalopram and citalopram, the S-DDCT and DDCT concentrations are well below the QTc prolonging concentrations reported in dogs. There is no strong evidence from human and animal studies that the cardiac safety of escitalopram is significantly superior to that of citalopram. Copyright 2012, SLACK Incorporated.

Escitalopram attenuates β-amyloid-induced tau hyperphosphorylation in primary hippocampal neurons through the 5-HT1A receptor mediated Akt/GSK-3β pathway

PubMed Central

Gong, Wei-Gang; Wu, Di; Tang, Xiang; Li, Xiao-Li; Wu, Fang-Fang; Bai, Feng; Xu, Lin; Zhang, Zhi-Jun

2016-01-01

Tau hyperphosphorylation is an important pathological feature of Alzheimer's disease (AD). To investigate whether escitalopram could inhibit amyloid-β (Aβ)-induced tau hyperphosphorylation and the underlying mechanisms, we treated the rat primary hippocampal neurons with Aβ1-42 and examined the effect of escitalopram on tau hyperphosphorylation. Results showed that escitalopram decreased Aβ1–42-induced tau hyperphosphorylation. In addition, escitalopram activated the Akt/GSK-3β pathway, and the PI3K inhibitor LY294002 blocked the attenuation of tau hyperphosphorylation induced by escitalopram. Moreover, the 5-HT1A receptor agonist 8-OH-DPAT also activated the Akt/GSK-3β pathway and decreased Aβ1-42-induced tau hyperphosphorylation. Furthermore, the 5-HT1A receptor antagonist WAY-100635 blocked the activation of Akt/GSK-3β pathway and the attenuation of tau hyperphosphorylation induced by escitalopram. Finally, escitalopram improved Aβ1–42 induced impairment of neurite outgrowth and spine density, and reversed Aβ1–42 induced reduction of synaptic proteins. Our results demonstrated that escitalopram attenuated Aβ1–42-induced tau hyperphosphorylation in primary hippocampal neurons through the 5-HT1A receptor mediated Akt/GSK-3β pathway. PMID:26950279

Escitalopram attenuates β-amyloid-induced tau hyperphosphorylation in primary hippocampal neurons through the 5-HT1A receptor mediated Akt/GSK-3β pathway.

PubMed

Wang, Yan-Juan; Ren, Qing-Guo; Gong, Wei-Gang; Wu, Di; Tang, Xiang; Li, Xiao-Li; Wu, Fang-Fang; Bai, Feng; Xu, Lin; Zhang, Zhi-Jun

2016-03-22

Tau hyperphosphorylation is an important pathological feature of Alzheimer's disease (AD). To investigate whether escitalopram could inhibit amyloid-β (Aβ)-induced tau hyperphosphorylation and the underlying mechanisms, we treated the rat primary hippocampal neurons with Aβ1-42 and examined the effect of escitalopram on tau hyperphosphorylation. Results showed that escitalopram decreased Aβ1-42-induced tau hyperphosphorylation. In addition, escitalopram activated the Akt/GSK-3β pathway, and the PI3K inhibitor LY294002 blocked the attenuation of tau hyperphosphorylation induced by escitalopram. Moreover, the 5-HT1A receptor agonist 8-OH-DPAT also activated the Akt/GSK-3β pathway and decreased Aβ1-42-induced tau hyperphosphorylation. Furthermore, the 5-HT1A receptor antagonist WAY-100635 blocked the activation of Akt/GSK-3β pathway and the attenuation of tau hyperphosphorylation induced by escitalopram. Finally, escitalopram improved Aβ1-42 induced impairment of neurite outgrowth and spine density, and reversed Aβ1-42 induced reduction of synaptic proteins. Our results demonstrated that escitalopram attenuated Aβ1-42-induced tau hyperphosphorylation in primary hippocampal neurons through the 5-HT1A receptor mediated Akt/GSK-3β pathway.

Pharmacotherapy Relapse Prevention in Body Dysmorphic Disorder: A Double-Blind Placebo-Controlled Trial

PubMed Central

Phillips, Katharine A.; Keshaviah, Aparna; Dougherty, Darin; Stout, Robert L.; Menard, William; Wilhelm, Sabine

2016-01-01

Objective Body dysmorphic disorder (BDD) is common, distressing, and often severely impairing. Serotonin-reuptake inhibitors (SRIs) appear efficacious for BDD, but the few existing pharmacotherapy studies were short-term (≤4 months), and no relapse prevention studies or continuation phase studies have been conducted. We report results from the first BDD relapse prevention study. Method Adults (N=100) with DSM-IV BDD received open-label escitalopram for 14 weeks (Phase 1); 58 responders were then randomized to double-blind continuation treatment with escitalopram versus switch to placebo for six months (Phase 2). Reliable and valid outcome measures were utilized. Results Phase 1: Overall, 67.0% of treated subjects and 81.1% of completers were escitalopram responders (p’s<0.0001). BDD severity, BDD-related insight, depressive symptoms, psychosocial functioning, and quality of life significantly improved from baseline to end of Phase 1 (all p's<0.0001). Phase 2: Time to relapse was significantly longer for subjects receiving escitalopram than those receiving placebo (hazard ratio=2.72, 95% CI [1.01, 8.57], p=0.049). Phase 2 relapse proportions were 18% for escitalopram versus 40% for placebo. In escitalopram-treated subjects, BDD severity significantly decreased over time during the continuation treatment phase (p=0.036); further improvement occurred in 35.7% of the escitalopram group. There were no significant group differences in BDD severity, insight, depressive symptoms, psychosocial functioning, or quality of life. Conclusions Continuation-phase escitalopram delayed time to relapse, and fewer escitalopram-treated subjects relapsed compared with placebo-treated subjects. BDD severity significantly further improved during six additional months of escitalopram treatment following acute response; more than one-third of escitalopram-treated subjects had further improvement during continuation phase treatment. PMID:27056606

The interaction of escitalopram and R-citalopram at the human serotonin transporter investigated in the mouse.

PubMed

Jacobsen, Jacob P R; Plenge, Per; Sachs, Benjamin D; Pehrson, Alan L; Cajina, Manuel; Du, Yunzhi; Roberts, Wendy; Rudder, Meghan L; Dalvi, Prachiti; Robinson, Taylor J; O'Neill, Sharon P; Khoo, King S; Morillo, Connie Sanchez; Zhang, Xiaodong; Caron, Marc G

2014-12-01

Escitalopram appears to be a superior antidepressant to racemic citalopram. It has been hypothesized that binding of R-citalopram to the serotonin transporter (SERT) antagonizes escitalopram binding to and inhibition of the SERT, there by curtailing the elevation of extracellular 5-hydroxytryptamine (5-HTExt), and hence anti-depressant efficacy. Further, it has been suggested that a putative allosteric binding site is important for binding of escitalopram to the primary, orthosteric, site, and for R-citalopram's inhibition here of. Primary: Investigate at the human (h)SERT, at clinical relevant doses, whether R-citalopram antagonizes escitalopram-induced 5-HTExt elevation. Secondary: Investigate whether abolishing the putative allosteric site affects escitalopram-induced 5-HTExt elevation and/or modulates the effect of R-citalopram. Recombinant generation of hSERT transgenic mice; in vivo microdialysis; SERT binding; pharmacokinetics; 5-HT sensitive behaviors (tail suspension, marble burying). We generated mice expressing either the wild-type human SERT (hSERT(WT)) or hSERT carrying amino acid substitutions (A505V, L506F, I507L, S574T and I575T) collectively abolishing the putative allosteric site (hSERT(ALI/VFL+SI/TT)). One mg/kg escitalopram yielded clinical relevant plasma levels and brain levels consistent with therapeutic SERT occupancy. The hSERT mice showed normal basal 5-HTExt levels. Escitalopram-induced 5-HTExt elevation was not decreased by R-citalopram co-treatment and was unaffected by loss of the allosteric site. The behavioral effects of the clinically relevant escitalopram dose were small and tended to be enhanced by R-citalopram co-administration. We find no evidence that R-citalopram directly antagonizes escitalopram or that the putative allosteric site is important for hSERT inhibition by escitalopram.

Escitalopram block of hERG potassium channels.

PubMed

Chae, Yun Ju; Jeon, Ji Hyun; Lee, Hong Joon; Kim, In-Beom; Choi, Jin-Sung; Sung, Ki-Wug; Hahn, Sang June

2014-01-01

Escitalopram, a selective serotonin reuptake inhibitor, is the pharmacologically active S-enantiomer of the racemic mixture of RS-citalopram and is widely used in the treatment of depression. The effects of escitalopram and citalopram on the human ether-a-go-go-related gene (hERG) channels expressed in human embryonic kidney cells were investigated using voltage-clamp and Western blot analyses. Both drugs blocked hERG currents in a concentration-dependent manner with an IC50 value of 2.6 μM for escitalopram and an IC50 value of 3.2 μM for citalopram. The blocking of hERG by escitalopram was voltage-dependent, with a steep increase across the voltage range of channel activation. However, voltage independence was observed over the full range of activation. The blocking by escitalopram was frequency dependent. A rapid application of escitalopram induced a rapid and reversible blocking of the tail current of hERG. The extent of the blocking by escitalopram during the depolarizing pulse was less than that during the repolarizing pulse, suggesting that escitalopram has a high affinity for the open state of the hERG channel, with a relatively lower affinity for the inactivated state. Both escitalopram and citalopram produced a reduction of hERG channel protein trafficking to the plasma membrane but did not affect the short-term internalization of the hERG channel. These results suggest that escitalopram blocked hERG currents at a supratherapeutic concentration and that it did so by preferentially binding to both the open and the inactivated states of the channels and by inhibiting the trafficking of hERG channel protein to the plasma membrane.

Ziprasidone Augmentation of Escitalopram for Major Depressive Disorder: Efficacy Results From a Randomized, Double-Blind, Placebo-Controlled Study.

PubMed

Papakostas, George I; Fava, Maurizio; Baer, Lee; Swee, Michaela B; Jaeger, Adrienne; Bobo, William V; Shelton, Richard C

2015-12-01

The authors sought to test the efficacy of adjunctive ziprasidone in adults with nonpsychotic unipolar major depression experiencing persistent symptoms after 8 weeks of open-label treatment with escitalopram. This was an 8-week, randomized, double-blind, parallel-group, placebo-controlled trial conducted at three academic medical centers. Participants were 139 outpatients with persistent symptoms of major depression after an 8-week open-label trial of escitalopram (phase 1), randomly assigned in a 1:1 ratio to receive adjunctive ziprasidone (escitalopram plus ziprasidone, N=71) or adjunctive placebo (escitalopram plus placebo, N=68), with 8 weekly follow-up assessments. The primary outcome measure was clinical response, defined as a reduction of at least 50% in score on the 17-item Hamilton Depression Rating Scale (HAM-D). The Hamilton Anxiety Rating scale (HAM-A) and Visual Analog Scale for Pain were defined a priori as key secondary outcome measures. Rates of clinical response (35.2% compared with 20.5%) and mean improvement in HAM-D total scores (-6.4 [SD=6.4] compared with -3.3 [SD=6.2]) were significantly greater for the escitalopram plus ziprasidone group. Several secondary measures of antidepressant efficacy also favored adjunctive ziprasidone. The escitalopram plus ziprasidone group also showed significantly greater improvement on HAM-A score but not on Visual Analog Scale for Pain score. Ten (14%) patients in the escitalopram plus ziprasidone group discontinued treatment because of intolerance, compared with none in the escitalopram plus placebo group. Ziprasidone as an adjunct to escitalopram demonstrated antidepressant efficacy in adult patients with major depressive disorder experiencing persistent symptoms after 8 weeks of open-label treatment with escitalopram.

The interaction of escitalopram and R-citalopram at the human serotonin transporter investigated in the mouse

PubMed Central

Jacobsen, Jacob P.R.; Plenge, Per; Sachs, Benjamin D.; Pehrson, Alan L.; Cajina, Manuel; Du, Yunzhi; Roberts, Wendy; Rudder, Meghan L.; Dalvi, Prachiti; Robinson, Taylor J.; O’Neill, Sharon P.; Khoo, King S.; Morillo, Connie Sanchez; Zhang, Xiaodong; Caron, Marc G.

2015-01-01

Rationale Escitalopram is a superior antidepressant to racemic citalopram. It has been hypothesized that binding of R-citalopram to the serotonin transporter (SERT) antagonizes escitalopram binding to and inhibition of the SERT, curtailing the elevation of extracellular 5-hydroxytryptamine (5-HTExt), and antidepressant efficacy. Further, it has been suggested that a putative allosteric binding site is important for binding of escitalopram to the primary, orthosteric, site, and for R-citalopram’s inhibition hereof. Objectives Primary: Investigate at the human (h)SERT, at clinical relevant doses, whether R-citalopram antagonizes escitalopram-induced 5-HTExt elevation. Secondary: Investigate whether abolishing the putative allosteric site affects escitalopram-induced 5-HTExt elevation and/or modulates the effect of R-citalopram. Methods Recombinant technology; in vivo microdialysis; receptor binding; pharmacokinetics; 5-HT sensitive behaviors (tail suspension, marble burying). Results We generated mice expressing either the wild-type human SERT (hSERTWT) or hSERT carrying amino acid substitutions (A505V, L506F, I507L, S574T and I575T) collectively abolishing the putative allosteric site (hSERTALI/VFL+SI/TT). One mg/kg escitalopram yielded clinical relevant plasma levels and brain levels consistent with therapeutic SERT occupancy. Importantly, escitalopram-induced 5-HTExt elevation was not decreased by R-citalopram co-treatment. Further, escitalopram-induced 5-HTExt elevation was not affected by loss of the allosteric site. The behavioral effects of the clinically relevant escitalopram dose were small, tending to be enhanced by R-citalopram co-administration. Conclusions We find no evidence that R-citalopram directly antagonizes escitalopram or that the putative allosteric site is important for hSERT inhibition by escitalopram. Our findings points to mechanisms for R-citalopram antagonism of escitalopram’s antidepressant action other than direct antagonistic binding interactions at the hSERT. PMID:24810106

Escitalopram in the Treatment of Adolescent Depression: A Randomized, Double-Blind, Placebo-Controlled Extension Trial

PubMed Central

Robb, Adelaide; Bose, Anjana

2013-01-01

Abstract Objective The purpose of this study was to evaluate the extended efficacy, safety, and tolerability of escitalopram relative to placebo in adolescents with major depressive disorder (MDD). Methods Adolescents (12–17 years) who completed an 8-week randomized, double-blind, flexible-dose, placebo-controlled, lead-in study of escitalopram 10–20 mg versus placebo could enroll in a 16–24-week, multisite extension trial; patients maintained the same lead-in randomization (escitalopram or placebo) and dosage (escitalopram 10 or 20 mg/day, or placebo) during the extension. The primary efficacy was Children's Depression Rating Scale-Revised (CDRS-R) change from the lead-in study baseline to treatment week 24 (8-week lead-in study plus 16-week extension); the secondary efficacy was Clinical Global Impressions-Improvement (CGI-I) score at week 24. All efficacy analyses used the last observation carried forward (LOCF) approach; sensitivity analyses used observed cases (OC) and mixed-effects model for repeated measures (MMRM). Safety was evaluated via adverse event (AE) reports and the clinician-rated Columbia-Suicide Severity Rating Scale (C-SSRS). Results Following lead-in, 165 patients enrolled in the double-blind extension (82 placebo; 83 escitalopram); 40 (48.8%) placebo and 37 (44.6%) escitalopram patients completed treatment. CDRS-R total score improvement was significantly greater for escitalopram than for placebo (p=0.005, LOCF; p=0.014; MMRM). Response rates (CDRS-R ≥40% reduction from baseline [adjusted and unadjusted] and CGI-I ≤2) were significantly higher for escitalopram than for placebo (LOCF); remission rates (CDRS-R ≤28) were 50.6% for escitalopram and 35.7% for placebo (p=0.002). OC analyses were not significantly different between groups. The most frequent escitalopram AEs (≥5% and more frequent than placebo) were headache, nausea, insomnia, vomiting, influenza-like symptoms, diarrhea, and urinary tract infection. Most AEs were mild/moderate and not related to the study drug. AEs suggestive of self-harm occurred in 5.7% and 7.1% of placebo and escitalopram patients. Occurrence of suicidal behavior and/or suicidal ideation assessed by C-SSRS was 10.9% (14/128) for placebo and 14.5% (19/131) for escitalopram. Conclusions Extended use of escitalopram was generally safe and resulted in modest improvement in efficacy in adolescents with MDD. PMID:24041408

Escitalopram in the treatment of adolescent depression: a randomized, double-blind, placebo-controlled extension trial.

PubMed

Findling, Robert L; Robb, Adelaide; Bose, Anjana

2013-09-01

The purpose of this study was to evaluate the extended efficacy, safety, and tolerability of escitalopram relative to placebo in adolescents with major depressive disorder (MDD). Adolescents (12-17 years) who completed an 8-week randomized, double-blind, flexible-dose, placebo-controlled, lead-in study of escitalopram 10-20 mg versus placebo could enroll in a 16-24-week, multisite extension trial; patients maintained the same lead-in randomization (escitalopram or placebo) and dosage (escitalopram 10 or 20 mg/day, or placebo) during the extension. The primary efficacy was Children's Depression Rating Scale-Revised (CDRS-R) change from the lead-in study baseline to treatment week 24 (8-week lead-in study plus 16-week extension); the secondary efficacy was Clinical Global Impressions-Improvement (CGI-I) score at week 24. All efficacy analyses used the last observation carried forward (LOCF) approach; sensitivity analyses used observed cases (OC) and mixed-effects model for repeated measures (MMRM). Safety was evaluated via adverse event (AE) reports and the clinician-rated Columbia-Suicide Severity Rating Scale (C-SSRS). Following lead-in, 165 patients enrolled in the double-blind extension (82 placebo; 83 escitalopram); 40 (48.8%) placebo and 37 (44.6%) escitalopram patients completed treatment. CDRS-R total score improvement was significantly greater for escitalopram than for placebo (p=0.005, LOCF; p=0.014; MMRM). Response rates (CDRS-R ≥ 40% reduction from baseline [adjusted and unadjusted] and CGI-I ≤ 2) were significantly higher for escitalopram than for placebo (LOCF); remission rates (CDRS-R ≤ 28) were 50.6% for escitalopram and 35.7% for placebo (p=0.002). OC analyses were not significantly different between groups. The most frequent escitalopram AEs (≥ 5% and more frequent than placebo) were headache, nausea, insomnia, vomiting, influenza-like symptoms, diarrhea, and urinary tract infection. Most AEs were mild/moderate and not related to the study drug. AEs suggestive of self-harm occurred in 5.7% and 7.1% of placebo and escitalopram patients. Occurrence of suicidal behavior and/or suicidal ideation assessed by C-SSRS was 10.9% (14/128) for placebo and 14.5% (19/131) for escitalopram. Extended use of escitalopram was generally safe and resulted in modest improvement in efficacy in adolescents with MDD.

Escitalopram, an antidepressant with an allosteric effect at the serotonin transporter--a review of current understanding of its mechanism of action.

PubMed

Zhong, Huailing; Haddjeri, Nasser; Sánchez, Connie

2012-01-01

Escitalopram is a widely used antidepressant for the treatment of patients with major depression. It is the pure S-enantiomer of racemic citalopram. Several clinical trials and meta-analyses indicate that escitalopram is quantitatively more efficacious than many other antidepressants with a faster onset of action. This paper reviews current knowledge about the mechanism of action of escitalopram. The primary target for escitalopram is the serotonin transporter (SERT), which is responsible for serotonin (or 5-hydroxytryptamine [5-HT]) reuptake at the terminals and cell bodies of serotonergic neurons. Escitalopram and selective serotonin reuptake inhibitors bind with high affinity to the 5-HT binding site (orthosteric site) on the transporter. This leads to antidepressant effects by increasing extracellular 5-HT levels which enhance 5-HT neurotransmission. SERT also has one or more allosteric sites, binding to which modulates activity at the orthosteric binding site but does not directly affect 5-HT reuptake by the transporter. In vitro studies have shown that through allosteric binding, escitalopram decreases its own dissociation rate from the orthosteric site on the SERT. R-citalopram, the nontherapeutic enantiomer in citalopram, is also an allosteric modulator of SERT but can inhibit the actions of escitalopram by interfering negatively with its binding. Both nonclinical studies and some clinical investigations have demonstrated the cellular, neurochemical, neuroadaptive, and neuroplastic changes induced by escitalopram with acute and chronic administration. The findings from binding, neurochemical, and neurophysiological studies may provide a mechanistic rationale for the clinical difference observed with escitalopram compared to other antidepressant therapies.

Escitalopram causes fewer seizures in human overdose than citalopram.

PubMed

Yilmaz, Zeynep; Ceschi, Alessandro; Rauber-Lüthy, Christine; Sauer, Oliver; Stedtler, Uwe; Prasa, Dagmar; Seidel, Carola; Hackl, Elisabeth; Hoffmann-Walbeck, Petra; Gerber-Zupan, Gabriela; Bauer, Kathrin; Kupferschmidt, Hugo; Kullak-Ublick, Gerd-Achim; Wilks, Martin

2010-03-01

Seizures are a recognized complication of acute overdose with the racemic (1:1 ratio of R- and S-enantiomers) selective serotonin reuptake inhibitor antidepressant citalopram. We tested the hypothesis that escitalopram (the therapeutically active S-enantiomer of citalopram) causes fewer seizures in overdose than citalopram at comparable doses of the S-enantiomer. Multicenter retrospective review of cases with citalopram and escitalopram overdose reported to German, Austrian, and Swiss Poisons Centers between 1997 and 2006. 316 citalopram and 63 escitalopram cases were analyzed. Somnolence, nausea, vomiting, tachycardia, QT prolongation, and tremor occurred with similar frequency in both groups. There was a striking difference in the frequency of single and multiple seizures: 43 cases (13.5%) in the citalopram group and 1 case (1.6%) with a single seizure in the escitalopram group (p=0.0065). At comparable ingested doses of the S-enantiomer, the symptom profile for citalopram and escitalopram intoxications is similar except for seizures that occur more frequently in citalopram than in escitalopram poisoning.

SSRI Effects on Psychomotor Performance: Assessment of Citalopram and Escitalopram on Normal Subjects

DTIC Science & Technology

2007-07-01

RESEARCH ARTICLE SSRI Effects on Pyschomotor Performance: Assessment of Citalopram and Escitalopram on Normal Subjects MICHEL A. PAUL, GARY W... escitalopram 011 nomral subjects. Aviat Space Environ Med 2007; 78:693-7. Introduction: Standard aeromedical doctrine dictates that aircrew...noradrenaline and dopamine reuptake inhibi- tor). This study was undertaken to determine whether or not cita lopram or escitalopram affect psychomotor

A randomized, double-blind, placebo-controlled study of escitalopram in patients with social anxiety disorder in Japan.

PubMed

Asakura, Satoshi; Hayano, Taiji; Hagino, Atsushi; Koyama, Tsukasa

2016-01-01

This randomized, double-blind placebo-controlled study compared the efficacy and tolerability of escitalopram (10 and 20 mg/day) in Japanese patients with social anxiety disorder (SAD). Patients aged 18-64 years with a primary diagnosis of DSM-IV-TR defined SAD, a Liebowitz Social Anxiety Scale Japanese version (LSAS-J) total score ≥60 and a Clinical Global Impression-Severity (CGI-S) score ≥4 at baseline were randomly assigned (1:1:1) to placebo, escitalopram 10 mg or escitalopram 20 mg. The primary endpoint was change from baseline to Week 12 in the LSAS-J total score for both escitalopram 10 mg and 20 mg versus placebo (ANCOVA, FAS, LOCF), using a hierarchical testing procedure. Pre-specified secondary endpoints included LSAS-J sensitivity analyses. This study has the www.japic.or.jp identifier: JapicCTI-121842. For the primary efficacy endpoint, the difference from placebo in the LSAS-J was -3.9 (p = 0.089) for escitalopram 10 mg. Since the superiority of escitalopram 10 mg over placebo was not confirmed, an analysis without multiplicity adjustment was made, which showed a difference for escitalopram 20 mg versus placebo of -9.8 (p < 0.001). In pre-specified sensitivity analyses, the difference versus placebo was -4.9 (p = 0.035) (ANCOVA, FAS, OC) and -5.0 (p = 0.028) (MMRM, FAS) (escitalopram 10 mg) and -10.1 (p < 0.001) (ANCOVA, FAS, OC) and -10.6 (p < 0.001) (MMRM, FAS) (escitalopram 20 mg). Common adverse events (incidence ≥5% and significantly different from placebo) were somnolence, nausea and ejaculation disorder. Escitalopram was efficacious, safe and well tolerated by patients with SAD in Japan. Study limitations are discussed including patient characteristics.

Effects of S-citalopram, citalopram, and R-citalopram on the firing patterns of dopamine neurons in the ventral tegmental area, N-methyl-D-aspartate receptor-mediated transmission in the medial prefrontal cortex and cognitive function in the rat.

PubMed

Schilström, Björn; Konradsson-Geuken, Asa; Ivanov, Vladimir; Gertow, Jens; Feltmann, Kristin; Marcus, Monica M; Jardemark, Kent; Svensson, Torgny H

2011-05-01

Escitalopram, the S-enantiomer of citalopram, possesses superior efficacy compared to other selective serotonin reuptake inhibitors (SSRIs) in the treatment of major depression. Escitalopram binds to an allosteric site on the serotonin transporter, which further enhances the blockade of serotonin reuptake, whereas R-citalopram antagonizes this positive allosteric modulation. Escitalopram's effects on neurotransmitters other than serotonin, for example, dopamine and glutamate, are not well studied. Therefore, we here studied the effects of escitalopram, citalopram, and R-citalopram on dopamine cell firing in the ventral tegmental area, using single-cell recording in vivo and on NMDA receptor-mediated currents in pyramidal neurons in the medial prefrontal cortex using in vitro electrophysiology in rats. The cognitive effects of escitalopram and citalopram were also compared using the novel object recognition test. Escitalopram (40-640 μg/kg i.v.) increased both firing rate and burst firing of dopaminergic neurons, whereas citalopram (80-1280 μg/kg) had no effect on firing rate and only increased burst firing at high dosage. R-citalopram (40-640 μg/kg) had no significant effects. R-citalopram (320 μg/kg) antagonized the effects of escitalopram (320 μg/kg). A very low concentration of escitalopram (5 nM), but not citalopram (10 nM) or R-citalopram (5 nM), potentiated NMDA-induced currents in pyramidal neurons. Escitalopram's effect was antagonized by R-citalopram and blocked by the dopamine D(1) receptor antagonist SCH23390. Escitalopram, but not citalopram, improved recognition memory. Our data suggest that the excitatory effect of escitalopram on dopaminergic and NMDA receptor-mediated neurotransmission may have bearing on its cognitive-enhancing effect and superior efficacy compared to other SSRIs in major depression. Copyright © 2010 Wiley-Liss, Inc.

Housing conditions modulate escitalopram effects on antidepressive-like behaviour and brain neurochemistry.

PubMed

Bjørnebekk, Astrid; Mathé, Aleksander A; Gruber, Susanne H M; Brené, Stefan

2008-12-01

Despite limited understanding of the pathophysiology of depression and the underlying mechanisms mediating antidepressant effects, there are several efficient treatments. The anhedonia symptoms of depression are characterized by decreased motivation and drive and imply possible malfunctioning of the mesolimbic dopamine system, whereas cognitive deficits might reflect decreased plasticity in hippocampus. In female Flinders Sensitive Line (FSL) rats, a model of depression, we compared the effects of three long-term antidepressant treatments: voluntary running, escitalopram and the combination of both on antidepressant-like behaviour in the Porsolt swim test (PST), and on regulation of mRNA for dopamine and neuropeptides in striatal dopamine pathways and brain-derived neurotrophic factor (BDNF) in hippocampus. Escitalopram diet attenuated running behaviour in FSL rats but not in non-depressed controls rats. In the PST the running group had increased climbing activity (noradrenergic/dopaminergic response), whereas the combination of escitalopram and running-wheel access increased swimming (serotonergic response). Running elevated mRNA for dynorphin in caudate putamen and BDNF in hippocampus. The combined treatment down-regulated D1 receptor and enkephalin mRNA in accumbens. Escitalopram alone did not affect behaviour or mRNA levels. We demonstrate a novel behavioural effect of escitalopram, i.e. attenuation of running in 'depressed' rats. The antidepressant-like effect of escitalopram was dependent on the presence of a running wheel, but not actual running indicating that the environment influenced the antidepressant effect of escitalopram. Different patterns of mRNA changes in hippocampus and brain reward pathways and responses in the PST by running and escitalopram suggest that antidepressant-like responses by running and escitalopram are achieved by different mechanisms.

Pharmacotherapy Relapse Prevention in Body Dysmorphic Disorder: A Double-Blind, Placebo-Controlled Trial.

PubMed

Phillips, Katharine A; Keshaviah, Aparna; Dougherty, Darin D; Stout, Robert L; Menard, William; Wilhelm, Sabine

2016-09-01

Body dysmorphic disorder is common, distressing, and often severely impairing. Serotonin reuptake inhibitors appear efficacious, but the few existing pharmacotherapy studies were short term (≤4 months), and no relapse prevention studies or continuation phase studies have been conducted to the authors' knowledge. The authors report results from the first relapse prevention study in body dysmorphic disorder. Adults (N=100) with DSM-IV body dysmorphic disorder received open-label escitalopram for 14 weeks (phase 1); 58 responders were then randomized to double-blind continuation treatment with escitalopram versus switch to placebo for 6 months (phase 2). Reliable and valid outcome measures were utilized. In phase 1, 67.0% of treated subjects and 81.1% of subjects who completed phase 1 responded to escitalopram. Body dysmorphic disorder severity (in both the intent-to-treat and the completer groups) and insight, depressive symptoms, psychosocial functioning, and quality of life significantly improved from baseline to end of phase 1. In phase 2, time to relapse was significantly longer with escitalopram than with placebo treatment (hazard ratio=2.72, 95% CI=1.01-8.57). Phase 2 relapse proportions were 18% for escitalopram and 40% for placebo. Among escitalopram-treated subjects, body dysmorphic disorder severity significantly decreased over time during the continuation phase, with 35.7% of subjects showing further improvement. There were no significant group differences in body dysmorphic disorder severity or insight, depressive symptoms, psychosocial functioning, or quality of life. Continuation-phase escitalopram delayed time to relapse, and fewer escitalopram-treated subjects relapsed than did placebo-treated subjects. Body dysmorphic disorder severity significantly improved during 6 additional months of escitalopram treatment following acute response; more than one-third of escitalopram-treated subjects experienced further improvement.

Blockade of the high-affinity noradrenaline transporter (NET) by the selective 5-HT reuptake inhibitor escitalopram: an in vivo microdialysis study in mice

PubMed Central

Nguyen, Hai T; Guiard, Bruno P; Bacq, Alexandre; David, Denis J; David, Indira; Quesseveur, Gaël; Gautron, Sophie; Sanchez, Connie; Gardier, Alain M

2013-01-01

BACKGROUND AND PURPOSE Escitalopram, the S(+)-enantiomer of citalopram is the most selective 5-HT reuptake inhibitor approved. Although all 5-HT selective reuptake inhibitors (SSRIs) increase extracellular levels of 5-HT ([5-HT]ext). some also enhance, to a lesser extent, extracellular levels of noradrenaline ([NA]ext). However, the mechanisms by which SSRIs activate noradrenergic transmission in the brain remain to be determined. EXPERIMENTAL APPROACH This study examined the effects of escitalopram, on both [5-HT]ext and [NA]ext in the frontal cortex (FCx) of freely moving wild-type (WT) and mutant mice lacking the 5-HT transporter (SERT−/−) by using intracerebral microdialysis. We explored the possibilities that escitalopram enhances [NA]ext, either by a direct mechanism involving the inhibition of the low- or high-affinity noradrenaline transporters, or by an indirect mechanism promoted by [5-HT]ext elevation. The forced swim test (FST) was used to investigate whether enhancing cortical [5-HT]ext and/or [NA]ext affected the antidepressant-like activity of escitalopram. KEY RESULTS In WT mice, a single systemic administration of escitalopram produced a significant increase in cortical [5-HT]ext and [NA]ext. As expected, escitalopram failed to increase cortical [5-HT]ext in SERT−/− mice, whereas its neurochemical effects on [NA]ext persisted in these mutants. In WT mice subjected to the FST, escitalopram increased swimming parameters without affecting climbing behaviour. Finally, escitalopram, at relevant concentrations, failed to inhibit cortical noradrenaline and 5-HT uptake mediated by low-affinity monoamine transporters. CONCLUSIONS AND IMPLICATIONS These experiments suggest that escitalopram enhances, although moderately, cortical [NA]extin vivo by a direct mechanism involving the inhibition of the high-affinity noradrenaline transporter (NET). PMID:22233336

Assessment of citalopram and escitalopram on neuroblastoma cell lines: Cell toxicity and gene modulation

PubMed Central

Sakka, Laurent; Delétage, Nathalie; Chalus, Maryse; Aissouni, Youssef; Sylvain-Vidal, Valérie; Gobron, Stéphane; Coll, Guillaume

2017-01-01

Selective serotonin reuptake inhibitors (SSRI) are common antidepressants which cytotoxicity has been assessed in cancers notably colorectal carcinomas and glioma cell lines. We assessed and compared the cytotoxicity of 2 SSRI, citalopram and escitalopram, on neuroblastoma cell lines. The study was performed on 2 non-MYCN amplified cell lines (rat B104 and human SH-SY5Y) and 2 human MYCN amplified cell lines (IMR32 and Kelly). Citalopram and escitalopram showed concentration-dependent cytotoxicity on all cell lines. Citalopram was more cytotoxic than escitalopram. IMR32 was the most sensitive cell line. The absence of toxicity on human primary Schwann cells demonstrated the safety of both molecules for myelin. The mechanisms of cytotoxicity were explored using gene-expression profiles and quantitative real-time PCR (qPCR). Citalopram modulated 1 502 genes and escitalopram 1 164 genes with a fold change ≥ 2. 1 021 genes were modulated by both citalopram and escitalopram; 481 genes were regulated only by citalopram while 143 genes were regulated only by escitalopram. Citalopram modulated 69 pathways (KEGG) and escitalopram 42. Ten pathways were differently modulated by citalopram and escitalopram. Citalopram drastically decreased the expression of MYBL2, BIRC5 and BARD1 poor prognosis factors of neuroblastoma with fold-changes of -107 (p<2.26 10−7), -24.1 (p<5.6 10−9) and -17.7 (p<1.2 10−7). CCNE1, AURKA, IGF2, MYCN and ERBB2 were more moderately down-regulated by both molecules. Glioma markers E2F1, DAPK1 and CCND1 were down-regulated. Citalopram displayed more powerful action with broader and distinct spectrum of action than escitalopram. PMID:28467792

Assessment of citalopram and escitalopram on neuroblastoma cell lines. Cell toxicity and gene modulation.

PubMed

Sakka, Laurent; Delétage, Nathalie; Chalus, Maryse; Aissouni, Youssef; Sylvain-Vidal, Valérie; Gobron, Stéphane; Coll, Guillaume

2017-06-27

Selective serotonin reuptake inhibitors (SSRI) are common antidepressants which cytotoxicity has been assessed in cancers notably colorectal carcinomas and glioma cell lines. We assessed and compared the cytotoxicity of 2 SSRI, citalopram and escitalopram, on neuroblastoma cell lines. The study was performed on 2 non-MYCN amplified cell lines (rat B104 and human SH-SY5Y) and 2 human MYCN amplified cell lines (IMR32 and Kelly). Citalopram and escitalopram showed concentration-dependent cytotoxicity on all cell lines. Citalopram was more cytotoxic than escitalopram. IMR32 was the most sensitive cell line. The absence of toxicity on human primary Schwann cells demonstrated the safety of both molecules for myelin. The mechanisms of cytotoxicity were explored using gene-expression profiles and quantitative real-time PCR (qPCR). Citalopram modulated 1 502 genes and escitalopram 1 164 genes with a fold change ≥ 2. 1 021 genes were modulated by both citalopram and escitalopram; 481 genes were regulated only by citalopram while 143 genes were regulated only by escitalopram. Citalopram modulated 69 pathways (KEGG) and escitalopram 42. Ten pathways were differently modulated by citalopram and escitalopram. Citalopram drastically decreased the expression of MYBL2, BIRC5 and BARD1 poor prognosis factors of neuroblastoma with fold-changes of -107 (p<2.26 10-7), -24.1 (p<5.6 10-9) and -17.7 (p<1.2 10-7). CCNE1, AURKA, IGF2, MYCN and ERBB2 were more moderately down-regulated by both molecules. Glioma markers E2F1, DAPK1 and CCND1 were down-regulated. Citalopram displayed more powerful action with broader and distinct spectrum of action than escitalopram.

Adjunctive aripiprazole therapy with escitalopram in patients with co-morbid major depressive disorder and alcohol dependence: Clinical and neuroimaging evidence

PubMed Central

Han, Doug Hyun; Kim, Sun Mi; Choi, Jung Eun; Min, Kyung Joon; Renshaw, Perry F.

2015-01-01

The effective treatment of depression has been reported to reduce the severity of alcohol use, potentially reflecting improvements in common brain reward circuits. We hypothesized that augmentation therapy of escitalopram with aripiprazole would improve depressive symptoms as well as reduce craving for alcohol and cue-induced brain activity in patients with co-morbid alcohol dependence and major depressive disorder, compared with treatment with escitalopram alone. Thirty-five subjects with major depressive disorder and alcohol dependence were recruited and randomly assigned into 17 aripiprazole + escitalopram and 18 escitalopram only groups. At baseline and following six weeks of treatment, symptoms of depression, craving for alcohol and brain activity were evaluated. During the six week treatment period, Beck Depression Inventory and clinical global index-severity (CGI-S) scores decreased in both the aripiprazole + escitalopram and escitalopram only groups. In addition, following the treatment period, the Korean alcohol urge questionnaire scores in the aripiprazole + escitalopram group were reduced from 23.3±8.4 to 14.3±4.9, compared with those of the escitalopram group of from 21.6±8.4 to 19.3±7.1 (F=13.1, p<0.01). The activity within the anterior cingulate was increased in response to the presentation of alcohol drinking scenes following treatment in the aripiprazole + escitalopram group. The change of brain activity within the left anterior cingulate gyrus in all patients with co-morbid alcohol dependence and major depressive disorder was negatively correlated with the change in craving for alcohol. These findings suggest that the effects of aripiprazole on anterior cingulate cortex might mediate the successful treatment of alcohol dependence in patients with major depressive disorder. PMID:23325372

Sodium channel blockade with QRS widening after an escitalopram overdose.

PubMed

Schreffler, Susan M; Marraffa, Jeanna M; Stork, Christine M; Mackey, Jennifer

2013-09-01

Escitalopram is rarely associated with prolongation of the QTc interval; however, there are no reported cases of QRS complex widening associated with escitalopram overdose. We report a case of a patient who presented with both QRS complex widening and QTc interval prolongation after an escitalopram overdose. A 16-year-old girl presented to the emergency department after ingestion of escitalopram, tramadol/acetaminophen, and hydrocodone/acetaminophen. Laboratory results were significant for 4-hour acetaminophen 21.1 μg/mL. Serum electrolytes including potassium, magnesium, and calcium were all normal. Initial electrocardiogram (ECG) revealed a widened QRS with an incomplete right bundle branch pattern. After administration of 100-mEq sodium bicarbonate, a repeat ECG revealed narrowing of the QRS complex and a prolonged QTc interval. Magnesium sulfate 2 g intravenous and sodium bicarbonate drip were initiated. A repeat ECG, 1 hour after the second, revealed normalization of the QRS complex and QTc interval. Prolongation of the QTc interval is an expected effect of escitalopram. Both escitalopram and citalopram are metabolized to the cardiotoxic metabolite S-didesmethylcitalopram and didesmethylcitalopram, respectively, which have been implicated in numerous cardiac abnormalities including widening of the QRS complex. Although never previously described with escitalopram, this mechanism provides a reasonable explanation for the QRS complex widening and incomplete right bundle branch block that occurred in our patient. Both QRS complex widening and QTc interval prolongation should be monitored in cases of escitalopram and citalopram overdoses.

Comparing the Effects of Bupropion and Escitalopram on Excessive Internet Game Play in Patients with Major Depressive Disorder.

PubMed

Nam, Beomwoo; Bae, Sujin; Kim, Sun Mi; Hong, Ji Seon; Han, Doug Hyun

2017-11-30

Several studies have suggested the efficacy of bupropion and escitalopram on reducing the excessive internet game play. We hypothesized that both bupropion and escitalopram would be effective on reducing the severity of depressive symptoms and internet gaming disorder (IGD) symptoms in patients with both major depressive disorder and IGD. However, the changes in brain connectivity between the default mode network (DMN) and the salience network were different between bupropion and escitalopram due to their different pharmacodynamics. This study was designed as a 12-week double blind prospective trial. Thirty patients were recruited for this research (15 bupropion group+15 escitalopram group). To assess the differential functional connectivity (FC) between the hubs of the DMN and the salience network, we selected 12 regions from the automated anatomical labeling in PickAtals software. After drug treatment, the depressive symptoms and IGD symptoms in both groups were improved. Impulsivity and attentional symptoms in the bupropion group were significantly decreased, compared to the escitalopram group. After treatment, FC within only the DMN in escitalopram decreased while FC between DMN and salience network in bupropion group decreased. Bupropion was associated with significantly decreased FC within the salience network and between the salience network and the DMN, compared to escitalopram. Bupropion showed greater effects than escitalopram on reducing impulsivity and attentional symptoms. Decreased brain connectivity between the salience network and the DMN appears to be associated with improved excessive IGD symptoms and impulsivity in MDD patients with IGD.

Effects of Cytochrome P450 (CYP) 2C19 Genotypes on Steady-State Plasma Concentrations of Escitalopram and its Desmethyl Metabolite in Japanese Patients With Depression.

PubMed

Tsuchimine, Shoko; Ochi, Shinichiro; Tajiri, Misuzu; Suzuki, Yutaro; Sugawara, Norio; Inoue, Yoshimasa; Yasui-Furukori, Norio

2018-06-01

Plasma concentrations of the S-enantiomer of citalopram were different between extensive and poor CYP2C19 metabolizers in healthy subjects and depressed patients. However, most studies applied dose-corrected concentrations. Thus, we studied the effects of polymorphisms of the CYP2C19 gene on raw plasma drug concentrations in Japanese patients with depression. Subjects in this study consisted of 412 depressed patients receiving 5, 10, 15, or 20 mg of escitalopram once a day. Plasma concentrations of escitalopram and desmethylescitalopram were quantified using HPLC. CYP2C19 genotypes were identified using polymerase chain reaction methods. There were no differences in the steady-state plasma concentrations of escitalopram or desmethylescitalopram in each dose group (5, 10, 15, or 20 mg of escitalopram) among CYP2C19 genotype groups. However, 1-way analysis of variance showed significant effects of CYP2C19 genotypes on the dose-adjusted plasma concentration of escitalopram but not in the dose-adjusted plasma concentration of desmethylescitalopram. Analysis of covariance including age, sex, and body weight showed significant effects of CYP2C19 genotypes on the dose-adjusted plasma concentration of escitalopram and the ratio of desmethylescitalopram to escitalopram. These findings suggest that the CYP2C19 variants are associated with steady-state plasma concentrations of escitalopram to some extent but are not associated with desmethylescitalopram.

A Review of Escitalopram and Citalopram in Child and Adolescent Depression

PubMed Central

Carandang, Carlo; Jabbal, Rekha; MacBride, Angela; Elbe, Dean

2011-01-01

Objective: To review the basic pharmacology and published literature regarding escitalopram and citalopram in child and adolescent depression. Methods: A literature review was conducted using the search terms: ‘escitalopram’, ‘citalopram’, ‘depression’, ‘randomized controlled trial’, ‘open label trial’ and limits set to: Human trials, English Language and All Child (Age 0–18). Additional articles were identified from reference information and poster presentation data. Results: Three prospective, randomized controlled trials (RCT) were found for escitalopram in pediatric depression, and two RCTs were found for citalopram. One RCT each for escitalopram and citalopram showed superiority over placebo on the primary out come measure. Adverse effects in escitalopram and citalopram trials were generally mild to moderate. Suicidality was not assessed systematically in all RCTs reviewed, but did not appear to be elevated over placebo in escitalopram RCTs. One trial reported numerically higher suicide related events for citalopram compared to placebo (14 vs. 5, p=0.06). Conclusion: At present, escitalopram and citalopram should be considered a second-line option for adolescent depression. The US Food and Drug Administration approval of escitalopram for treatment of adolescent depression was based on a single positive RCT. This is less evidence than typically required for approval of a drug for a new indication. PMID:22114615

A comparative review of escitalopram, paroxetine, and sertraline: are they all alike?

PubMed Central

Reines, Elin H.; Montgomery, Stuart A.

2014-01-01

It is known that newer antidepressants, such as the selective serotonin reuptake inhibitors (SSRIs), provide advantages in tolerability over antidepressants such as the tricyclics. However, even within the SSRI class, differences in efficacy or tolerability exist between the individual drugs. Among the three most widely prescribed SSRIs are paroxetine, sertraline, and escitalopram. Escitalopram is commonly referred to as an SSRI, but also has well-documented allosteric properties, and thus can be further classed as an allosteric serotonin reuptake inhibitor. All three antidepressants are efficacious compared with placebo, but there is evidence that escitalopram is more effective than a range of other antidepressants. There are no direct data to regard either paroxetine or sertraline as a superior antidepressant. Escitalopram is superior compared with paroxetine, which has a less favorable tolerability profile. Paroxetine is associated with cholinergic muscarinic antagonism and potent inhibition of CYP2D6, and sertraline has moderate drug interaction issues in comparison with escitalopram. Overall, as an allosteric serotonin reuptake inhibitor that is somewhat different from classical SSRIs, escitalopram is the first choice judged by combined efficacy and tolerability, and nonclinical data have offered possible mechanisms through which escitalopram could be more efficacious, based on its interaction with orthosteric and allosteric binding sites at the serotonin transporter. PMID:24424469

A comparative review of escitalopram, paroxetine, and sertraline: Are they all alike?

PubMed

Sanchez, Connie; Reines, Elin H; Montgomery, Stuart A

2014-07-01

It is known that newer antidepressants, such as the selective serotonin reuptake inhibitors (SSRIs), provide advantages in tolerability over antidepressants such as the tricyclics. However, even within the SSRI class, differences in efficacy or tolerability exist between the individual drugs. Among the three most widely prescribed SSRIs are paroxetine, sertraline, and escitalopram. Escitalopram is commonly referred to as an SSRI, but also has well-documented allosteric properties, and thus can be further classed as an allosteric serotonin reuptake inhibitor. All three antidepressants are efficacious compared with placebo, but there is evidence that escitalopram is more effective than a range of other antidepressants. There are no direct data to regard either paroxetine or sertraline as a superior antidepressant. Escitalopram is superior compared with paroxetine, which has a less favorable tolerability profile. Paroxetine is associated with cholinergic muscarinic antagonism and potent inhibition of CYP2D6, and sertraline has moderate drug interaction issues in comparison with escitalopram. Overall, as an allosteric serotonin reuptake inhibitor that is somewhat different from classical SSRIs, escitalopram is the first choice judged by combined efficacy and tolerability, and nonclinical data have offered possible mechanisms through which escitalopram could be more efficacious, based on its interaction with orthosteric and allosteric binding sites at the serotonin transporter.

Anhedonia among patients with Major Depressive Disorder: A comparison between patients on escitalopram and healthy controls.

PubMed

Ng, C G; Wong, S K; Loh, H S; Yee, A

Escitalopram has widely been recognized as one of the most frequently used antidepressants, with superior tolerability and great efficacy in preventing major depressive disorder (MDD) relapse and recurrence. However, anhedonia, which is a core symptom of MDD, remains difficult to treat. This study investigates the hedonic levels of MDD patients treated with Escitalopram. A total of 108 participants, 26 of whom with MDD on Escitalopram, were recruited in this cross sectional study. They were evaluated using the Snaith-Hamilton Pleasure Scale (SHAPS) and Beck Depression Inventory (BDI) questionnaires to assess their hedonic state, general mental health condition and level of depression. Our study shows that most items in the SHAPS scores are significantly different between MDD patients on Escitalopram and the controls. The hedonic capacity remains different between the two groups despite patients with MDD are put on Escitalopram treatment. Escitalopram fails to alleviate the hedonic state of MDD patients. Antidepressants that improve both depressive symptoms and hedonic states should be considered when treating MDD patients in clinical settings.

The effects of escitalopram on myocardial apoptosis and the expression of Bax and Bcl-2 during myocardial ischemia/reperfusion in a model of rats with depression.

PubMed

Wang, Yiming; Zhang, Hongming; Chai, Fangxian; Liu, Xingde; Berk, Michael

2014-12-04

Major depressive disorder (MDD) is an independent risk factor for coronary heart disease (CHD), and influences the occurrence and prognosis of cardiovascular events. Although there is evidence that antidepressants may be cardioprotective after acute myocardial infarction (AMI) comorbid with MDD, the operative pathophysiological mechanisms remain unclear. Our aim was therefore to explore the molecular mechanisms of escitalopram on myocardial apoptosis and the expression of Bax and Bcl-2 in a rat model of depression during myocardial ischemia/reperfusion (I/R). Rats were divided randomly into 3 groups (n = 8): D group (depression), DI/R group (depression with myocardial I/R) and escitalopram + DI/R group. The rats in all three groups underwent the same chronic mild stress and separation for 21 days, at the same time, in the escitalopram + DI/R group, rats were administered escitalopram by gavage (10 mg/kg/day). Ligation of the rat's left anterior descending branch was done in the myocardial I/R model. Following which behavioral tests were done. The size of the myocardial infarction was detected using 1.5% TTC dye. The Tunel method was used to detect apoptotic myocardial cells, and both the Rt-PCR method and immunohistochemical techniques were used to detect the expression of Bcl-2 and Bax. Compared with the D and DI/R groups, rats in Escitalopram + DI/R group showed significantly increased movements and sucrose consumption (P < .01). Compared with the DI/R group, the myocardial infarct size in the escitalopram + DI/R group was significantly decreased (P < .01). Compared with the D group, there were significantly increased apoptotic myocardial cells in the DI/R and escitalopram + DI/R groups (P < .01); however compared with the DI/R group, apoptotic myocardial cell numbers in the escitalopram + DI/R group were significantly decreased (P < .01). Compared with the DI/R group, there was a down-regulated Bax:Bcl-2 ratio in the escitalopram + DI/R group (P < .01). These results suggest that in patients with AMI comorbid with MDD, there is an increase in pro-apoptotic pathways that is reversed by escitalopram. This suggests that clinically escitalopram may have a direct cardioprotective after acute myocardial infarction.

Comparative study of the effects of bupropion and escitalopram on Internet gaming disorder.

PubMed

Song, Jinuk; Park, Jeong Ha; Han, Doug Hyun; Roh, Sungwon; Son, Ji Hyun; Choi, Tae Young; Lee, Hyuk; Kim, Tae Ho; Lee, Young Sik

2016-11-01

We compared the efficacy of bupropion and escitalopram treatments in Internet gaming disorder (IGD) patients. We recruited 119 adolescents and adults with IGD. We treated these participants for 6 weeks in three groups as follows: 44 participants were treated with bupropion SR (bupropion group), 42 participants were treated with escitalopram (escitalopram group), and 33 patients without any medication were observed in the community (observation group). At baseline and at the 6-week follow-up visit, all subjects were evaluated using the Clinical Global Impression-Severity Scale, the Young Internet Addiction Scale, the Beck Depression Inventory, the ADHD Rating Scale, and the Behavioral Inhibition and Activation Scales. Both the escitalopram group and the bupropion group showed improvement on all clinical symptom scales after 6 weeks of treatment compared to the observation group. Additionally, the bupropion group showed greater improvement on scores for the Clinical Global Impression-Severity Scale, the Young Internet Addiction Scale, the ADHD Rating Scale, and the Behavioral Inhibition Scale than the escitalopram group. Both bupropion and escitalopram were effective in treating and managing IGD symptoms. Moreover, bupropion appeared to be more effective than escitalopram in improving attention and impulsivity in IGD patients. In addition, attention and impulsivity seem to be important for the management of IGD. © 2016 The Authors. Psychiatry and Clinical Neurosciences © 2016 Japanese Society of Psychiatry and Neurology.

The Effects of Fluvoxamine on the Steady-State Plasma Concentrations of Escitalopram and Desmethylescitalopram in Depressed Japanese Patients.

PubMed

Yasui-Furukori, Norio; Tsuchimine, Shoko; Kubo, Kazutoshi; Ishioka, Masamichi; Nakamura, Kazuhiko; Inoue, Yoshimasa

2016-08-01

The aim of this study was to determine the impact of fluvoxamine, an inhibitor of Cytochrome P450 (CYP) 2C19 (CYP2C19), on the pharmacokinetics of escitalopram, a substrate of CYP2C19. Thirteen depressed patients initially received a 20-mg/d dose of escitalopram alone. Subsequently, a 50-mg/d dose of fluvoxamine was administered because of the insufficient efficacy of escitalopram. Plasma concentrations of escitalopram and desmethylescitalopram were quantified using high-performance liquid chromatography before and after fluvoxamine coadministration. The QT and corrected QT (QTc) intervals were measured before and after fluvoxamine coadministration. Fluvoxamine significantly increased the plasma concentrations of escitalopram (72.3 ± 36.9 ng/mL versus 135.2 ± 79.7 ng/mL, P < 0.01) but not those of desmethylescitalopram (21.5 ± 7.0 ng/mL versus 24.9 ± 12.0 ng/mL, no significance [ns]). The ratios of desmethylescitalopram to escitalopram were significantly decreased during fluvoxamine coadministration (0.37 ± 0.21 versus 0.21 ± 0.10, P < 0.01). The CYP2C19 genotype did not fully explain the degree of the change. Fluvoxamine coadministration did not change the QT or QTc intervals. The results of this study suggest that adjunctive treatment with fluvoxamine increases the concentration of escitalopram. The QTc interval did not change in this condition.

Differential regulation of serotonin-1A receptor-stimulated [35S]GTP gamma S binding in the dorsal raphe nucleus by citalopram and escitalopram.

PubMed

Rossi, Dania V; Burke, Teresa F; Hensler, Julie G

2008-03-31

The effect of chronic citalopram or escitalopram administration on 5-HT1A receptor function in the dorsal raphe nucleus was determined by measuring [35S]GTP gamma S binding stimulated by the 5-HT1A receptor agonist (R)-(+)-8-OH-DPAT (1nM-10 microM). Although chronic administration of citalopram or escitalopram has been shown to desensitize somatodendritic 5-HT1A autoreceptors, we found that escitalopram treatment decreased the efficacy of 5-HT1A receptors to activate G proteins, whereas citalopram treatment did not. The binding of [3H]8-OH-DPAT to the coupled, high affinity agonist state of the receptor was not altered by either treatment. Interestingly, escitalopram administration resulted in greater occupancy of serotonin transporter sites as measured by the inhibition of [3H]cyanoimipramine binding. As the binding and action of escitalopram is limited by the inactive enantiomer R-citalopram present in racemic citalopram, we propose that the regulation of 5-HT1A receptor function in the dorsal raphe nucleus at the level of receptor-G protein interaction may be a result of greater inhibition of the serotonin transporter by escitalopram.

Differential regulation of serotonin-1A receptor stimulated [35S]GTPγS binding in the dorsal raphe nucleus by citalopram and escitalopram

PubMed Central

Rossi, Dania V.; Burke, Teresa F.; Hensler, Julie G.

2008-01-01

The effect of chronic citalopram or escitalopram administration on 5-HT1A receptor function in the dorsal raphe nucleus was determined by measuring [35S]GTPγS binding stimulated by the 5-HT1A receptor agonist (R)-(+)-8-OH-DPAT (1nM-10μM). Although chronic administration of citalopram or escitalopram has been shown to desensitize somatodendritic 5-HT1A autoreceptors, we found that escitalopram treatment decreased the efficacy of 5-HT1A receptors to activate G-proteins, whereas citalopram treatment did not. The binding of [3H]8-OH-DPAT to the coupled, high affinity agonist state of the receptor was not altered by either treatment. Interestingly, escitalopram administration resulted in greater occupancy of serotonin transporter sites as measured by the inhibition of [3H]cyanoimipramine binding. As the binding and action of escitalopram is limited by the inactive enantiomer R-citalopram present in racemic citalopram, we propose that the regulation of 5-HT1A receptor function in the dorsal raphe nucleus at the level of receptor-G protein interaction may be a result of greater inhibition of the serotonin transporter by escitalopram. PMID:18289523

Responder analysis for pain relief and numbers needed to treat in a meta-analysis of etoricoxib osteoarthritis trials: bridging a gap between clinical trials and clinical practice

PubMed Central

Moore, R A; Moore, O A; Derry, S; Peloso, P M; Gammaitoni, A R; Wang, H

2010-01-01

Background: Population mean changes from clinical trials are difficult to apply to individuals in clinical practice. Responder analysis may be better, but needs validating for level of response and treatment duration. Methods: The numbers of patients with pain relief over baseline (⩾15%, ⩾30%, ⩾50%, ⩾70%) at 2, 4, 8 and 12 weeks of treatment were obtained using the WOMAC 100 mm visual analogue pain subscale score for each treatment group in seven randomised placebo-controlled trials of etoricoxib in osteoarthritis lasting ⩾6 weeks. Dropouts were assigned 0% improvement from baseline from then on. The numbers needed to treat (NNTs) were calculated at each level of response and time point. Results: 3554 patients were treated with placebo, etoricoxib 30 mg and 60 mg, celecoxib 200 mg, naproxen 1000 mg or ibuprofen 2400 mg daily. Response rates fell with increasing pain relief: 60–80% experienced minimally important pain relief (⩾15%), 50–60% moderate pain relief (⩾30%), 40–50% substantial pain relief (⩾50%) and 20–30% extensive pain relief (⩾70%). NNTs for etoricoxib, celecoxib and naproxen were stable over 2–12 weeks. Ibuprofen showed lessening of effectiveness with time. Conclusion: Responder rates and NNTs are reproducible for different levels of response over 12 weeks and have relevance for clinical practice at the individual patient level. An average 10 mm improvement in pain equates to almost one in two patients having substantial benefit. PMID:19364730

Spotlight on escitalopram in the management of major depressive disorder.

PubMed

Murdoch, David; Keam, Susan J

2006-01-01

Escitalopram (Cipralex), Lexapro), the active S-enantiomer of the racemic SSRI citalopram (RS-citalopram), is a highly selective inhibitor of the serotonin transporter protein. It possesses a rapid onset of antidepressant activity, and is an effective and generally well tolerated treatment for moderate-to-severe major depressive disorder (MDD). Pooled analyses from an extensive clinical trial database suggest that escitalopram is consistently more effective than citalopram in moderate-to-severe MDD. Preliminary studies suggest that escitalopram is as effective as other SSRIs and the extended-release (XR) formulation of the serotonin/noradrenaline (norepinephrine) reuptake inhibitor venlafaxine, and may have cost-effectiveness and cost-utility advantages. However, additional longer-term, comparative studies evaluating specific efficacy, tolerability, health-related quality of life and economic indices would be helpful in definitively positioning escitalopram relative to these other agents in the treatment of MDD. Nevertheless, available clinical and pharmacoeconomic data indicate that escitalopram is an effective first-line option in the management of patients with MDD.

Escitalopram: a review of its use in the management of major depressive disorder.

PubMed

Murdoch, David; Keam, Susan J

2005-01-01

Escitalopram (Cipralex, Lexapro), the active S-enantiomer of the racemic selective serotonin reuptake inhibitor (SSRI) citalopram (RS-citalopram), is a highly selective inhibitor of the serotonin transporter protein. It possesses a rapid onset of antidepressant activity, and is an effective and generally well tolerated treatment for moderate-to-severe major depressive disorder (MDD). Pooled analyses from an extensive clinical trial database suggest that escitalopram is consistently more effective than citalopram in moderate-to-severe MDD. Preliminary studies suggest that escitalopram is as effective as other SSRIs and the extended-release (XR) formulation of the serotonin/noradrenaline (norepinephrine) reuptake inhibitor venlafaxine, and may have cost-effectiveness and cost-utility advantages. However, additional longer-term, comparative studies evaluating specific efficacy, tolerability, health-related quality of life and economic indices would be helpful in definitively positioning escitalopram relative to these other agents in the treatment of MDD. Nevertheless, available clinical and pharmacoeconomic data indicate that escitalopram is an effective first-line option in the management of patients with MDD.

No effect of escitalopram versus placebo on brain-derived neurotrophic factor in healthy individuals: a randomised trial.

PubMed

Knorr, Ulla; Koefoed, Pernille; Soendergaard, Mia H Greisen; Vinberg, Maj; Gether, Ulrik; Gluud, Christian; Wetterslev, Jørn; Winkel, Per; Kessing, Lars V

2016-04-01

Brain-derived neurotrophic factor (BDNF) seems to play an important role in the course of depression including the response to antidepressants in patients with depression. We aimed to study the effect of an antidepressant intervention on peripheral BDNF in healthy individuals with a family history of depression. We measured changes in BDNF messenger RNA (mRNA) expression and whole-blood BDNF levels in 80 healthy first-degree relatives of patients with depression randomly allocated to receive daily tablets of escitalopram 10 mg versus placebo for 4 weeks. We found no statistically significant difference between the escitalopram and the placebo group in the change in BDNF mRNA expression and whole-blood BDNF levels. Post hoc analyses showed a statistically significant negative correlation between plasma escitalopram concentration and change in whole-blood BDNF levels in the escitalopram-treated group. The results of this randomised trial suggest that escitalopram 10 mg has no effect on peripheral BDNF levels in healthy individuals.

From selective to highly selective SSRIs: a comparison of the antinociceptive properties of fluoxetine, fluvoxamine, citalopram and escitalopram.

PubMed

Schreiber, Shaul; Pick, Chaim G

2006-08-01

Most Serotonin Selective Reuptake Inhibitors (SSRIs) have been found to possess secondary binding properties, while citalopram and its S-enantiomer (escitalopram) have been reconfirmed "purest SSRIs". Using the mouse model of acute pain hotplate analgesia meter, we evaluated the antinociceptive properties of fluoxetine, fluvoxamine, citalopram and escitalopram, injected i.p. Fluvoxamine induced a dose-dependent clear antinociceptive effect (with an ED(50) value of 6.4 mg/kg). Both fluoxetine and citalopram induced (separately) only a weak antinociceptive effect with an inverse "U" shape curve. All three drug's effects were not abolished by naloxone. Escitalopram did not elicit any effect at quasi-equipotent doses. These findings show that fluoxetine, fluvoxamine and citalopram given i.p. are weak antinociceptors, (not mediated through opioid mechanisms), while escitalopram possesses no antinociceptive properties when injected i.p. This difference between citalopram and escitalopram calls for further studies in order to assess the various differences between the two enantiomers of citalopram, and between each enantiomer and the racemic mixture.

Escitalopram prolonged fear induced by simulated public speaking and released hypothalamic-pituitary-adrenal axis activation.

PubMed

Garcia-Leal, C; Del-Ben, C M; Leal, F M; Graeff, F G; Guimarães, F S

2010-05-01

Simulated public speaking (SPS) test is sensitive to drugs that interfere with serotonin-mediated neurotransmission and is supposed to recruit neural systems involved in panic disorder. The study was aimed at evaluating the effects of escitalopram, the most selective serotonin-selective reuptake inhibitor available, in SPS. Healthy males received, in a double-blind, randomized design, placebo (n = 12), 10 (n = 17) or 20 (n = 14) mg of escitalopram 2 hours before the test. Behavioural, autonomic and neuroendocrine measures were assessed. Both doses of escitalopram did not produce any effect before or during the speech but prolonged the fear induced by SPS. The test itself did not significantly change cortisol and prolactin levels but under the higher dose of escitalopram, cortisol and prolactin increased immediately after SPS. This fear-enhancing effect of escitalopram agrees with previously reported results with less selective serotonin reuptake inhibitors and the receptor antagonist ritanserin, indicating that serotonin inhibits the fear of speaking in public.

Prospective, multicentre, randomized, double-blind study of the efficacy of escitalopram versus citalopram in outpatient treatment of major depressive disorder.

PubMed

Moore, Nicholas; Verdoux, Hélène; Fantino, Bruno

2005-05-01

Pre-clinical studies, active-control clinical trials and meta-analyses indicate that escitalopram (S-citalopram) might be more effective than citalopram, the racemic mixture of S- and R-citalopram. The present study aimed to confirm the superior efficacy of escitalopram over citalopram. A double-blind, randomized clinical trial was performed in which general practitioners and psychiatrists compared fixed doses of escitalopram (20 mg/day) with citalopram (40 mg/day) over 8 weeks in outpatients with major depressive disorder (MDD) [baseline Montgomery-Asberg Depression Rating Scale (MADRS) score > or =30]. Primary efficacy parameter was change from baseline to last assessment in the MADRS total score. Out of 138 (aged 44.1+/-10.9 years; initial MADRS score 36.3+/-4.8) and 142 (aged 46.2+/-11.1 years; initial MADRS score 35.7+/-4.4) evaluable patients who were randomized to escitalopram and citalopram, respectively, six and 15 withdrew prematurely (P=0.05). The MADRS score decreased more in the escitalopram than in the citalopram arm (-22.4+/-12.9 versus -20.3+/-12.7; P<0.05). There were more treatment responders with escitalopram (76.1%) than with citalopram (61.3%, P<0.01). Adjusted remitter rates were 56.1% and 43.6%, respectively (P<0.05). Tolerability was similar in both groups. This randomized double-blind trial confirms that escitalopram has a superior effect to citalopram in MDD.

Escitalopram Ameliorates Tau Hyperphosphorylation and Spatial Memory Deficits Induced by Protein Kinase A Activation in Sprague Dawley Rats.

PubMed

Ren, Qing-Guo; Wang, Yan-Juan; Gong, Wei-Gang; Xu, Lin; Zhang, Zhi-Jun

2015-01-01

Here, we investigated the effect of escitalopram pretreatment on protein kinase A (PKA)-induced tau hyperphosphorylation and spatial memory deficits in rats using western blot and behavioral tests, respectively. We demonstrated that escitalopram effectively ameliorated tau hyperphosphorylation and the spatial memory deficits induced by PKA activation. We measured the total and activity-dependent Ser9-phosphorylated levels of glycogen synthase kinase (GSK)-3β in hippocampal extracts. No significant change in the total level of GSK-3β was observed between the different groups. However, compared with forskolin injection alone, pretreatment with escitalopram increased the level of Ser9-phosphorylated GSK-3β. We also demonstrated that escitalopram increased Akt phosphorylation at Ser473 (the active form of Akt). Furthermore, we identified other important kinases and phosphatases, such as protein phosphatase 2A, extracellular signal-regulated kinases 1 and 2, and MAP kinase kinase-1/2, that have previously been reported to play a crucial role in tau phosphorylation; however, we did not detect any significant change in the activation of these kinases or phosphatases in our study. We unexpectedly demonstrated that forskolin caused anxiety-like behavior in rats, and pretreatment with escitalopram did not significantly ameliorate the anxiety-like behavior induced by forskolin. These data provide the first evidence that escitalopram ameliorates forskolin-induced tau hyperphosphorylation and spatial memory impairment in rats; these effects do not occur via the anti-anxiety activity of escitalopram but may involve the Akt/GSK-3β signaling pathway.

Pre- and post-treatments with escitalopram protect against experimental ischemic neuronal damage via regulation of BDNF expression and oxidative stress.

PubMed

Lee, Choong Hyun; Park, Joon Ha; Yoo, Ki-Yeon; Choi, Jung Hoon; Hwang, In Koo; Ryu, Pan Dong; Kim, Do-Hoon; Kwon, Young-Guen; Kim, Young-Myeong; Won, Moo-Ho

2011-06-01

Selective serotonin re-uptake inhibitors (SSRI) have been widely used in treatment of major depression because of their efficacy, safety, and tolerability. Escitalopram, an SSRI, is known to decrease oxidative stress in chronic stress animal models. In the present study, we examined the neuroprotective effects of pre- and post-treatments with 20 mg/kg and 30 mg/kg escitalopram in the gerbil hippocampal CA1 region (CA1) after transient cerebral ischemia. Pre-treatment with escitalopram protected against ischemia-induced neuronal death in the CA1 after ischemia/reperfusion (I/R). Post-treatment with 30 mg/kg, not 20 mg/kg, escitalopram had a neuroprotective effect against ischemic damage. In addition, 20 mg/kg pre- and 30 mg/kg post-treatments with escitalopram increased brain-derived neurotrophic factor (BDNF) protein levels in the ischemic CA1 compared to vehicle-treated ischemia animals. In addition, 20 mg/kg pre- and 30 mg/kg post-treatments with escitalopram reduced microglia activation and decreased 4-hydroxy-2-nonenal and Cu,Zn-superoxide dismutase immunoreactivity and their levels in the ischemic CA1 compared to vehicle-treated ischemia animals after transient cerebral ischemia. In conclusion, these results indicated that pre- and post-treatments with escitalopram can protect against ischemia-induced neuronal death in the CA1 induced by transient cerebral ischemic damage by increase of BDNF as well as decrease of microglia activation and oxidative stress. Copyright © 2011 Elsevier Inc. All rights reserved.

Micelle Enhanced Fluorimetric and Thin Layer Chromatography Densitometric Methods for the Determination of (±) Citalopram and its S – Enantiomer Escitalopram

PubMed Central

Taha, Elham A.; Salama, Nahla N.; Wang, Shudong

2009-01-01

Two sensitive and validated methods were developed for determination of a racemic mixture citalopram and its enantiomer S-(+) escitalopram. The first method was based on direct measurement of the intrinsic fluorescence of escitalopram using sodium dodecyl sulfate as micelle enhancer. This was further applied to determine escitalopram in spiked human plasma, as well as in the presence of common and co-administerated drugs. The second method was TLC densitometric based on various chiral selectors was investigated. The optimum TLC conditions were found to be sensitive and selective for identification and quantitative determination of enantiomeric purity of escitalopram in drug substance and drug products. The method can be useful to investigate adulteration of pure isomer with the cheap racemic form. PMID:19652757

Micelle enhanced fluorimetric and thin layer chromatography densitometric methods for the determination of (+/-) citalopram and its S-enantiomer escitalopram.

PubMed

Taha, Elham A; Salama, Nahla N; Wang, Shudong

2009-04-07

Two sensitive and validated methods were developed for determination of a racemic mixture citalopram and its enantiomer S-(+) escitalopram. The first method was based on direct measurement of the intrinsic fluorescence of escitalopram using sodium dodecyl sulfate as micelle enhancer. This was further applied to determine escitalopram in spiked human plasma, as well as in the presence of common and co-administrated drugs. The second method was TLC densitometric based on various chiral selectors was investigated. The optimum TLC conditions were found to be sensitive and selective for identification and quantitative determination of enantiomeric purity of escitalopram in drug substance and drug products. The method can be useful to investigate adulteration of pure isomer with the cheap racemic form.

The selective serotonin reuptake inhibitor, escitalopram, enhances inhibition of prepotent responding and spatial reversal learning

PubMed Central

Brown, Holden D.; Amodeo, Dionisio A.; Sweeney, John A.; Ragozzino, Michael E.

2011-01-01

Previous findings indicate treatment with a selective serotonin reuptake inhibitor (SSRI) facilitates behavioral flexibility when conditions require inhibition of a learned response pattern. The present experiment investigated whether acute treatment with the SSRI, escitalopram, affects behavioral flexibility when conditions require inhibition of a naturally-biased response pattern (elevated conflict test) and/or reversal of a learned response pattern (spatial reversal learning). An additional experiment was carried out to determine whether escitalopram, at doses that affected behavioral flexibility, also reduced anxiety as tested in the elevated plus-maze. In each experiment, Long-Evans rats received an intraperitoneal injection of either saline or escitalopram (0.03, 0.3 or 1.0 mg/kg) 30 minutes prior to behavioral testing. Escitalopram, at all doses tested, enhanced acquisition in the elevated conflict test, but did not affect performance in the elevated plus-maze. Escitalopram (0.3 and 1.0 mg/kg) did not alter acquisition of the spatial discrimination, but facilitated reversal learning. In the elevated conflict and spatial reversal learning test, escitalopram enhanced the ability to maintain the relevant strategy after being initially selected. The present findings suggest that enhancing serotonin transmission with a SSRI facilitates inhibitory processes when conditions require a shift away from either a naturally-biased response pattern or a learned choice pattern. PMID:22219222

Effect of short-term escitalopram treatment on neural activation during emotional processing.

PubMed

Maron, Eduard; Wall, Matt; Norbury, Ray; Godlewska, Beata; Terbeck, Sylvia; Cowen, Philip; Matthews, Paul; Nutt, David J

2016-01-01

Recent functional magnetic resonance (fMRI) imaging studies have revealed that subchronic medication with escitalopram leads to significant reduction in both amygdala and medial frontal gyrus reactivity during processing of emotional faces, suggesting that escitalopram may have a distinguishable modulatory effect on neural activation as compared with other serotonin-selective antidepressants. In this fMRI study we aimed to explore whether short-term medication with escitalopram in healthy volunteers is associated with reduced neural response to emotional processing, and whether this effect is predicted by drug plasma concentration. The neural response to fearful and happy faces was measured before and on day 7 of treatment with escitalopram (10mg) in 15 healthy volunteers and compared with those in a control unmedicated group (n=14). Significantly reduced activation to fearful, but not to happy facial expressions was observed in the bilateral amygdala, cingulate and right medial frontal gyrus following escitalopram medication. This effect was not correlated with plasma drug concentration. In accordance with previous data, we showed that escitalopram exerts its rapid direct effect on emotional processing via attenuation of neural activation in pathways involving medial frontal gyrus and amygdala, an effect that seems to be distinguishable from that of other SSRIs. © The Author(s) 2015.

Escitalopram versus other antidepressive agents for depression.

PubMed

Cipriani, Andrea; Santilli, Claudio; Furukawa, Toshi A; Signoretti, Alessandra; Nakagawa, Atsuo; McGuire, Hugh; Churchill, Rachel; Barbui, Corrado

2009-04-15

Although pharmacological and psychological interventions are both effective for major depression, antidepressant drugs remain the mainstay of treatment in primary and secondary care settings. During the last 20 years, antidepressant prescribing has risen dramatically in western countries, mainly because of the increasing consumption of selective serotonin reuptake inhibitors (SSRIs) and newer antidepressants, which have progressively become the most commonly prescribed antidepressants. Escitalopram is the pure S-enantiomer of the racemic citalopram. To assess the evidence for the efficacy, acceptability and tolerability of escitalopram in comparison with tricyclics, other SSRIs, heterocyclics and newer agents in the acute-phase treatment of major depression. Electronic databases were searched up to July 2008. Trial databases of drug-approving agencies were hand-searched for published, unpublished and ongoing controlled trials. All randomised controlled trials comparing escitalopram against any other antidepressant (including non-conventional agents such as hypericum) for patients with major depressive disorder (regardless of the diagnostic criteria used). Data were entered by two review authors (double data entry). Responders and remitters to treatment were calculated on an intention-to-treat basis. For dichotomous data, odds ratios (ORs) were calculated with 95% confidence intervals (CI). Continuous data were analysed using standardised mean differences (with 95% CI) using the random effects model. Fourteen trials compared escitalopram with another SSRI and eight compared escitalopram with a newer antidepressive agent (venlafaxine, bupropion and duloxetine). Escitalopram was shown to be significantly more effective than citalopram in achieving acute response (OR 0.67, 95% CI 0.50 to 0.87). Escitalopram was also more effective than citalopram in terms of remission (OR 0.53, 95% CI 0.30 to 0.93). Significantly fewer patients allocated to escitalopram withdrew from trials compared with patients allocated to duloxetine, for discontinuation due to any cause (OR 0.62, 95% CI 0.38 to 0.99). Some statistically significant differences favouring escitalopram over other antidepressive agents for the acute phase treatment of major depression were found, in terms of efficacy (citalopram and fluoxetine) and acceptability (duloxetine). There is insufficient evidence to detect a difference between escitalopram and other antidepressants in early response to treatment (after two weeks of treatment). Cost-effectiveness information is also needed in the field of antidepressant trials. Furthermore, as with most standard systematic reviews, the findings rely on evidence from direct comparisons. The potential for overestimation of treatment effect due to sponsorship bias should also be borne in mind.

Escitalopram dose-response revisited: an alternative psychometric approach to evaluate clinical effects of escitalopram compared to citalopram and placebo in patients with major depression.

PubMed

Bech, Per; Tanghøj, Per; Cialdella, Philippe; Andersen, Henning Friis; Pedersen, Anders Gersel

2004-09-01

In continuation of a previous psychometric analysis of dose-response data for citalopram in depression, the corresponding study data for escitalopram is of interest, since escitalopram is the active enantiomer of citalopram and because citalopram was used as the active control. Revisiting those corresponding data, the psychometric properties of the Montgomery-Asberg Depression Scale (MADRS) and the Hamilton Depression Scale (HAMD) were investigated by focusing on the unidimensional HAMD6 and MADRS6. Effect sizes were calculated and compared for two dosages of escitalopram (10 mg and 20 mg daily) and between each of these two dosages and 40 mg citalopram daily. The results showed that the three depression scales MADRS6, MADRS10 and HAMD6 were psychometrically acceptable (coefficient of homogeneity of 0.40 or higher). In the severely depressed patients (MADRS10> or =30) a rather clear dose-response relationship for escitalopram was seen on all three scales after 6 and 8 wk of therapy. Thus, the effect size for 10 mg escitalopram ranged from 0.28 to 0.38 while the effect sizes for 20 mg escitalopram ranged from 0.57 to 0.77. This difference was statistically significant (p<0.01). The effect size for 40 mg citalopram ranged from 0.36 to 0.47, which is within the range found for 40 mg citalopram in our previous dose-response analysis of citalopram after 6 wk of therapy. The numerically largest difference between 20 mg escitalopram and 40 mg citalopram was seen after 8 wk of therapy for MADRS10 (effect size 0.71 vs. 0.37). An item analysis identified 'suicidal thoughts' to be the most discriminating item in this respect. These results for the severely depressed patients were confirmed by the patients self-reported quality of life evaluation. When all included patients were analysed, however, no clear dose-response relationship was seen. In conclusion, a dose-response relationship for escitalopram was seen in the severely depressed patients on all outcome scales after 6 and 8 wk of treatment. After 8 wk of treatment 20 mg escitalopram was superior to 40 mg citalopram, but not after 2 wk of treatment.

The psychoactive drug Escitalopram affects swimming behaviour and increases boldness in zebrafish (Danio rerio).

PubMed

Nielsen, Sebastian V; Kellner, Martin; Henriksen, Per G; Olsén, Håkan; Hansen, Steen H; Baatrup, Erik

2018-05-01

Selective serotonin re-uptake inhibitors are pharmaceuticals used to treat a range of psychological disorders. They are frequently found in surface waters in populated areas. In recent years, they have been shown to affect the behaviour of various aquatic organisms in a way that can have ecological effects. In this study, we exposed zebrafish of both sexes to nominally 0.00, 0.15 and 1.50 µg L -1 Escitalopram in flow-through tanks for three weeks. Subsequently, ten swimming behaviour parameters were quantified using high-resolution video tracking. There were noticeable gender differences in the behaviour responses to Escitalopram. Female fish exposed to 1.50 µg L -1 Escitalopram had a lower maximum swimming velocity, stopped less often and exhibited increased boldness (reduced thigmotaxis) compared to controls. Male fish exposed to 1.50 µg L -1 had a lower maximum swimming velocity compared to control fish. At the end of exposures, both length and weight of the females exposed to 1.50 µg L -1 Escitalopram were significantly less than the group of control fish. In addition, males exposed to 1.50 µg L -1 Escitalopram were significantly shorter than control fish. The behaviour, weight and body length of the fish exposed to nominally 0.15 µg L -1 was not significantly different from control fish in either sex. The results of this study demonstrate that Escitalopram can affect subtle but ecologically important aspects of fish behaviour and lends further credibility to the assumption that Escitalopram is an environmentally active pharmaceutical.

Combining escitalopram and cognitive-behavioural therapy for social anxiety disorder: randomised controlled fMRI trial.

PubMed

Gingnell, Malin; Frick, Andreas; Engman, Jonas; Alaie, Iman; Björkstrand, Johannes; Faria, Vanda; Carlbring, Per; Andersson, Gerhard; Reis, Margareta; Larsson, Elna-Marie; Wahlstedt, Kurt; Fredrikson, Mats; Furmark, Tomas

2016-09-01

Selective serotonin reuptake inhibitors (SSRIs) and cognitive-behavioural therapy (CBT) are often used concomitantly to treat social anxiety disorder (SAD), but few studies have examined the effect of this combination. To evaluate whether adding escitalopram to internet-delivered CBT (ICBT) improves clinical outcome and alters brain reactivity and connectivity in SAD. Double-blind, randomised, placebo-controlled neuroimaging trial of ICBT combined either with escitalopram (n = 24) or placebo (n = 24), including a 15-month clinical follow-up (trial registration: ISRCTN24929928). Escitalopram+ICBT, relative to placebo+ICBT, resulted in significantly more clinical responders, larger reductions in anticipatory speech state anxiety at post-treatment and larger reductions in social anxiety symptom severity at 15-month follow-up and at a trend-level (P = 0.09) at post-treatment. Right amygdala reactivity to emotional faces also decreased more in the escitalopram+ICBT combination relative to placebo+ICBT, and in treatment responders relative to non-responders. Adding escitalopram improves the outcome of ICBT for SAD and decreased amygdala reactivity is important for anxiolytic treatment response. © The Royal College of Psychiatrists 2016.

Escitalopram treatment of depression in human immunodeficiency virus/acquired immunodeficiency syndrome: a randomized, double-blind, placebo-controlled study.

PubMed

Hoare, Jacqueline; Carey, Paul; Joska, John A; Carrara, Henri; Sorsdahl, Katherine; Stein, Dan J

2014-02-01

Depression can be a chronic and impairing illness in people with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome. Large randomized studies of newer selective serotonin reuptake inhibitors such as escitalopram in the treatment of depression in HIV, examining comparative treatment efficacy and safety, have yet to be done in HIV-positive patients. This was a fixed-dose, placebo-controlled, randomized, double-blind study to investigate the efficacy of escitalopram in HIV-seropositive subjects with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, major depressive disorder. One hundred two participants were randomly assigned to either 10 mg of escitalopram or placebo for 6 weeks. An analysis of covariance of the completers found that there was no advantage for escitalopram over placebo on the Montgomery-Asberg Depression Rating Scale (p = 0.93). Sixty-two percent responded to escitalopram and 59% responded to placebo on the Clinical Global Impression Scale. Given the relatively high placebo response, future trials in this area need to be selective in participant recruitment and to be adequately powered.

Effects of escitalopram, R-citalopram, and reboxetine on serum levels of tumor necrosis factor-α, interleukin-10, and depression-like behavior in mice after lipopolysaccharide administration.

PubMed

Dong, Chao; Zhang, Ji-chun; Yao, Wei; Ren, Qian; Yang, Chun; Ma, Min; Han, Mei; Saito, Ryo; Hashimoto, Kenji

2016-05-01

Inflammation plays a role in the pathophysiology of depression. The purpose of this study is to examine whether the selective serotonin reuptake inhibitor (SSRI) escitalopram, its inactive enantiomer R-citalopram, and selective noradrenaline reuptake inhibitor (NRI) reboxetine, show anti-inflammatory and antidepressant effects in an inflammation-induced model of depression. Pretreatment with escitalopram (1, 3, or 10mg/kg, i.p.) markedly blocked an increase in the serum levels of pro-inflammatory cytokine, tumor necrosis factor-α (TNF-α), after a single administration of lipopolysaccharide (LPS; 0.5mg/kg). Furthermore, escitalopram (3 or 10mg/kg) significantly increased the serum levels of the anti-inflammatory cytokine interleukin-10 (IL-10) by a single administration of LPS. In contrast, pretreatment with R-citalopram (10mg/kg, i.p.) or reboxetine (10mg/kg, i.p.) did not affect the alterations in serum levels of TNF-α and IL-10 after LPS administration. Co-administration of reboxetine with escitalopram did not show anti-inflammatory effects. Pretreatment with escitalopram (10mg/kg) significantly attenuated LPS-induced increase of the immobility time in the tail-suspension test (TST) and forced swimming test (FST). In contrast, pretreatment with R-citalopram (10mg/kg), or reboxetine (10mg/kg) did not alter LPS-induced increase of immobility time of TST and FST. Interestingly, co-administration of reboxetine with escitalopram did not show antidepressant effect in this model. These findings suggest that escitalopram, but not R-citalopram and reboxetine, has anti-inflammatory and antidepressant effects in LPS-treated model of depression, and that reboxetine can antagonize the effects of escitalopram in the inflammation model. Therefore, it is likely that serotonergic system plays a key role in the pathophysiology of inflammation-induced depression. Copyright © 2016 Elsevier Inc. All rights reserved.

Better sexual acceptability of agomelatine (25 and 50 mg) compared to escitalopram (20 mg) in healthy volunteers. A 9-week, placebo-controlled study using the PRSexDQ scale.

PubMed

Montejo, Angel L; Deakin, J F W; Gaillard, Raphael; Harmer, Catherine; Meyniel, Florent; Jabourian, Artin; Gabriel, Cecilia; Gruget, Celine; Klinge, Corinna; MacFayden, Christine; Milligan, Holly; Mullings, Emma; Goodwin, Guy

2015-10-01

The present double-blind, placebo-controlled study evaluates the effects of agomelatine and the selective serotonin reuptake inhibitor escitalopram on sexual dysfunction in healthy men and women. A total of 133 healthy volunteers (67 men, 66 women) were randomly assigned to agomelatine (25 or 50 mg) or escitalopram (20 mg) or placebo for nine weeks. Sexual acceptability was evaluated by using the psychotropic-related sexual dysfunction questionnaire 5-items total score and sexual dysfunction relative to each sub-score (in 110 volunteers with sexual activity). Sexual dysfunction was evaluated at baseline and after two, five and eight weeks of treatment and one week after drug discontinuation. The psychotropic-related sexual dysfunction questionnaire 5-items total score was significantly lower in both agomelatine groups versus escitalopram at all visits (p < 0.01 to p < 0.0001) with no difference between agomelatine and placebo nor between both agomelatine doses. Similar results were observed after drug discontinuation. The total score was significantly higher in the escitalopram group than in the placebo group at each post-baseline visit (p < 0.01 to p < 0.001). Similar results were observed regardless of volunteers' gender. Compared to placebo, only escitalopram significantly impaired dysfunction relative to "delayed orgasm or ejaculation" (p < 0.01) and "absence of orgasm or ejaculation" (p < 0.05 to p < 0.01). The percentage of participants with a sexual dysfunction was higher in the escitalopram group than in agomelatine groups (p < 0.01 to p < 0.05) and placebo (p < 0.01). The study confirms the better sexual acceptability profile of agomelatine (25 or 50 mg) in healthy men and women, compared to escitalopram. Evaluation of the effect of agomelatine and escitalopram on emotions and motivation in healthy male and female volunteers. ISRCTN75872983. © The Author(s) 2015.

Trial of Electrical Direct-Current Therapy versus Escitalopram for Depression.

PubMed

Brunoni, Andre R; Moffa, Adriano H; Sampaio-Junior, Bernardo; Borrione, Lucas; Moreno, Marina L; Fernandes, Raquel A; Veronezi, Beatriz P; Nogueira, Barbara S; Aparicio, Luana V M; Razza, Lais B; Chamorro, Renan; Tort, Luara C; Fraguas, Renerio; Lotufo, Paulo A; Gattaz, Wagner F; Fregni, Felipe; Benseñor, Isabela M

2017-06-29

We compared transcranial direct-current stimulation (tDCS) with a selective serotonin-reuptake inhibitor for the treatment of depression. In a single-center, double-blind, noninferiority trial involving adults with unipolar depression, we randomly assigned patients to receive tDCS plus oral placebo, sham tDCS plus escitalopram, or sham tDCS plus oral placebo. The tDCS was administered in 30-minute, 2-mA prefrontal stimulation sessions for 15 consecutive weekdays, followed by 7 weekly treatments. Escitalopram was given at a dose of 10 mg per day for 3 weeks and 20 mg per day thereafter. The primary outcome measure was the change in the 17-item Hamilton Depression Rating Scale (HDRS-17) score (range, 0 to 52, with higher scores indicating more depression). Noninferiority of tDCS versus escitalopram was defined by a lower boundary of the confidence interval for the difference in the decreased score that was at least 50% of the difference in the scores with placebo versus escitalopram. A total of 245 patients underwent randomization, with 91 being assigned to escitalopram, 94 to tDCS, and 60 to placebo. In the intention-to-treat analysis, the mean (±SD) decrease in the score from baseline was 11.3±6.5 points in the escitalopram group, 9.0±7.1 points in the tDCS group, and 5.8±7.9 points in the placebo group. The lower boundary of the confidence interval for the difference in the decrease for tDCS versus escitalopram (difference, -2.3 points; 95% confidence interval [CI], -4.3 to -0.4; P=0.69) was lower than the noninferiority margin of -2.75 (50% of placebo minus escitalopram), so noninferiority could not be claimed. Escitalopram and tDCS were both superior to placebo (difference vs. placebo, 5.5 points [95% CI, 3.1 to 7.8; P<0.001] and 3.2 points [95% CI, 0.7 to 5.5; P=0.01], respectively). Patients receiving tDCS had higher rates of skin redness, tinnitus, and nervousness than did those in the other two groups, and new-onset mania developed in 2 patients in the tDCS group. Patients receiving escitalopram had more frequent sleepiness and obstipation than did those in the other two groups. In a single-center trial, tDCS for the treatment of depression did not show noninferiority to escitalopram over a 10-week period and was associated with more adverse events. (Funded by Fundação de Amparo à Pesquisa do Estado de São Paulo and others; ELECT-TDCS ClinicalTrials.gov number, NCT01894815 .).

The influence of baseline severity on efficacy of escitalopram and citalopram in the treatment of major depressive disorder: an extended analysis.

PubMed

Lam, R W; Andersen, H F

2006-09-01

To determine the differences between escitalopram and citalopram in the treatment of patients with major depressive disorder across a range of baseline severity of depression using trend analysis. Data from the three placebo-controlled studies comparing escitalopram to citalopram were analyzed. The pre-specified primary outcome variable was MADRS total score; secondary outcomes included Clinical Global Impression-Severity (CGI-S) and -Improvement (CGI-I) scores. All analyses were based on an intent-to-treat (ITT) population and all direct comparisons were done by ANCOVA adjusting for baseline value and centre. Analyses of the pooled data (N=1203) show that, while the difference between citalopram and placebo was approximately constant across the range of baseline severity, the difference between escitalopram and placebo (p=0.0010 for no trend) and between escitalopram and citalopram (p=0.0012 for no trend) became greater, the more severely depressed the patients were at baseline. A similar pattern was apparent with the CGI-S and CGI-I results. There was a significant superiority of escitalopram over citalopram in response rate (defined as > or = 50% decrease in MADRS total score), and this difference increased with increasing baseline severity. These trend analyses thus indicate that the superiority of escitalopram over citalopram is more apparent as the baseline severity of depression increases.

A Double-Blind, Randomized, Placebo-Controlled Trial of Escitalopram in the Treatment of Pediatric Depression

ERIC Educational Resources Information Center

Wagner, Karen Dineen; Jonas, Jeffrey; Findling, Robert L.; Ventura, Daniel; Saikali, Khalil

2006-01-01

Objective: Escitalopram is a selective serotonin reuptake inhibitor antidepressant indicated for use in adults. This trial examined the efficacy and safety of escitalopram in pediatric depression. Method: Patients (6-17 years old) with major depressive disorder were randomized to receive 8 weeks of double-blind flexibly dosed treatment with…

Escitalopram versus other antidepressive agents for depression

PubMed Central

Cipriani, Andrea; Santilli, Claudio; Furukawa, Toshi A; Signoretti, Alessandra; Nakagawa, Atsuo; McGuire, Hugh; Churchill, Rachel; Barbui, Corrado

2014-01-01

Background Although pharmacological and psychological interventions are both effective for major depression, antidepressant drugs remain the mainstay of treatment in primary and secondary care settings. During the last 20 years, antidepressant prescribing has risen dramatically in western countries, mainly because of the increasing consumption of selective serotonin reuptake inhibitors (SSRIs) and newer antidepressants, which have progressively become the most commonly prescribed antidepressants. Escitalopram is the pure S-enantiomer of the racemic citalopram. Objectives To assess the evidence for the efficacy, acceptability and tolerability of escitalopram in comparison with tricyclics, other SSRIs, heterocyclics and newer agents in the acute-phase treatment of major depression. Search methods Electronic databases were searched up to July 2008. Trial databases of drug-approving agencies were hand-searched for published, unpublished and ongoing controlled trials. Selection criteria All randomised controlled trials comparing escitalopram against any other antidepressant (including non-conventional agents such as hypericum) for patients with major depressive disorder (regardless of the diagnostic criteria used). Data collection and analysis Data were entered by two review authors (double data entry). Responders and remitters to treatment were calculated on an intention-to-treat basis. For dichotomous data, odds ratios (ORs) were calculated with 95% confidence intervals (CI). Continuous data were analysed using standardised mean differences (with 95% CI) using the random effects model. Main results Fourteen trials compared escitalopram with another SSRI and eight compared escitalopram with a newer antidepressive agent (venlafaxine, bupropion and duloxetine). Escitalopram was shown to be significantly more effective than citalopram in achieving acute response (OR 0.67, 95% CI 0.50 to 0.87). Escitalopram was also more effective than citalopram in terms of remission (OR 0.53, 95% CI 0.30 to 0.93). Significantly fewer patients allocated to escitalopram withdrew from trials compared with patients allocated to duloxetine, for discontinuation due to any cause (OR 0.62, 95% CI 0.38 to 0.99). Authors’ conclusions Some statistically significant differences favouring escitalopram over other antidepressive agents for the acute phase treatment of major depression were found, in terms of efficacy (citalopram and fluoxetine) and acceptability (duloxetine). There is insufficient evidence to detect a difference between escitalopram and other antidepressants in early response to treatment (after two weeks of treatment). Cost-effectiveness information is also needed in the field of antidepressant trials. Furthermore, as with most standard systematic reviews, the findings rely on evidence from direct comparisons. The potential for overestimation of treatment effect due to sponsorship bias should also be borne in mind. PMID:19370639

Treatment with escitalopram improves the attentional bias toward negative facial expressions in patients with major depressive disorders.

PubMed

Zhou, Zhenhe; Cao, Suxia; Li, Hengfen; Li, Youhui

2015-10-01

We hypothesized that treatment with escitalopram would improve cognitive bias and contribute to the recovery process for patients with major depressive disorder (MDD). Many previous studies have established that patients with MDD tend to pay selective attention to negative stimuli. The assessment of the level of cognitive bias is regarded as a crucial dimension of treatment outcomes for MDD. To our knowledge, no prior studies have been reported on the effects of treatment with escitalopram on attentional bias in MDD, employing a dot probe task of facial expression. We studied 25 patients with MDD and 25 controls, and used a dot probe task of facial expression to measure cognitive bias. The patients' psychopathologies were rated using the Hamilton Depression Scale (HAMD) at baseline and after 8 weeks of treatment with escitalopram. All participants performed the facial expression dot probe task. The results revealed that the 8 week escitalopram treatment decreased the HAMD scores. The patients with MDD at baseline exhibited an attentional bias towards negative faces, however, no significant bias toward either negative or happy faces were observed in the controls. After the 8 week escitalopram treatment, no significant bias toward negative faces was observed in the patient group. In conclusion, patients with MDD pay more attention to negative facial expressions, and treatment with escitalopram improves this attentional bias toward negative facial expressions. This is the first study, to our knowledge, on the effects of treatment with escitalopram on attentional bias in patients with MDD that has employed a dot probe task of facial expression. Copyright © 2015 Elsevier Ltd. All rights reserved.

A randomized, double-blind, 24-week study of escitalopram (10 mg/day) versus citalopram (20 mg/day) in primary care patients with major depressive disorder.

PubMed

Colonna, Lucien; Andersen, Henning Friis; Reines, Elin Heldbo

2005-10-01

A randomized, double-blind, 24-week-fixed-dose study comparing the efficacy and safety of escitalopram to that of citalopram was safety was conducted in primary care patients with moderate to severe major depressive disorder (MDD). This was a randomized, double-blind, 24-week fixeddose study. Patients were randomly assigned to treatment with escitalopram 10 mg/day (n = 175) or citalopram 20 mg/day (n = 182). Clinical response was evaluated using the Montgomery-Asberg Depression Rating Scale (MADRS) and Clinical Global Impression-Severity (CGI-S) scale. The prospectively defined primary parameter of antidepressant efficacy was the change from baseline in the mean MADRS total score during the 24 weeks of double-blind treatment, using a repeated measures analysis of variance to compare the treatment groups over all assessment points simultaneously. Based on the primary parameter, escitalopram was at least as efficacious as citalopram. Based on the prospectively defined secondary parameter, mean change from baseline in the CGI-S score, escitalopram was statistically significantly superior to citalopram at Week 24. The importance of long-term treatment could be demonstrated, in that more than half (55% and 51%) of the patients who had not responded by Week 8 achieved remission by Week 24. Both escitalopram and citalopram were safe and well tolerated in acute and long-term treatment, and the overall adverse event profiles for the two drugs were similar. For the intent-to-treat population, there were statistically significantly fewer withdrawals in the escitalopram group than in the citalopram group, particularly after Week 8. Patients with MDD responded well to long-term treatment with either escitalopram or citalopram. This study demonstrated the importance of extending treatment of depression beyond 8 weeks.

Effects of acute and long-term administration of escitalopram and citalopram on serotonin neurotransmission: an in vivo electrophysiological study in rat brain.

PubMed

El Mansari, Mostafa; Sánchez, Connie; Chouvet, Guy; Renaud, Bernard; Haddjeri, Nasser

2005-07-01

The present study was undertaken to compare the acute and long-term effects of escitalopram and citalopram on rat brain 5-HT neurotransmission, using electrophysiological techniques. In hippocampus, after 2 weeks of treatment with escitalopram (10 mg/kg/day, s.c.) or citalopram (20 mg/kg/day, s.c.), the administration of the selective 5-HT(1A) receptor antagonist WAY-100,635 (20-100 microg/kg, i.v.) dose-dependently induced a similar increase in the firing activity of dorsal hippocampus CA(3) pyramidal neurons, thus revealing direct functional evidence of an enhanced tonic activation of postsynaptic 5-HT(1A) receptors. In dorsal raphe nucleus, escitalopram was four times more potent than citalopram in suppressing the firing activity of presumed 5-HT neurons (ED(50)=58 and 254 mug/kg, i.v., respectively). Interestingly, the suppressant effect of escitalopram (100 microg/kg, i.v.) was significantly prevented, but not reversed by R-citalopram (250 microg/kg, i.v.). Sustained administration of escitalopram and citalopram significantly decreased the spontaneous firing activity of presumed 5-HT neurons. This firing activity returned to control rate after 2 weeks in rats treated with escitalopram, but only after 3 weeks using citalopram, and was associated with a desensitization of somatodendritic 5-HT(1A) autoreceptors. These results suggest that the time course of the gradual return of presumed 5-HT neuronal firing activity, which was reported to account for the delayed effect of SSRI on 5-HT transmission, is congruent with the earlier onset of action of escitalopram vs citalopram in validated animal models of depression and anxiety.

An allosteric binding site at the human serotonin transporter mediates the inhibition of escitalopram by R-citalopram: kinetic binding studies with the ALI/VFL-SI/TT mutant.

PubMed

Zhong, Huailing; Hansen, Kasper B; Boyle, Noel J; Han, Kiho; Muske, Galina; Huang, Xinyan; Egebjerg, Jan; Sánchez, Connie

2009-10-25

The human serotonin transporter (hSERT) has primary and allosteric binding sites for escitalopram and R-citalopram. Previous studies have established that the interaction of these two compounds at a low affinity allosteric binding site of hSERT can affect the dissociation of [(3)H]escitalopram from hSERT. The allosteric binding site involves a series of residues in the 10th, 11th, and 12th trans-membrane domains of hSERT. The low affinity allosteric activities of escitalopram and R-citalopram are essentially eliminated in a mutant hSERT with changes in some of these residues, namely A505V, L506F, I507L, S574T, I575T, as measured in dissociation binding studies. We confirm that in association binding experiments, R-citalopram at clinically relevant concentrations reduces the association rate of [(3)H]escitalopram as a ligand to wild type hSERT. We demonstrate that the ability of R-citalopram to reduce the association rate of escitalopram is also abolished in the mutant hSERT (A505V, L506F, I507L, S574T, I575T), along with the expected disruption the low affinity allosteric function on dissociation binding. This suggests that the allosteric binding site mediates both the low affinity and higher affinity interactions between R-citalopram, escitalopram, and hSERT. Our data add an additional structural basis for the different efficacies of escitalopram compared to racemic citalopram reported in animal studies and clinical trials, and substantiate the hypothesis that hSERT has complex allosteric mechanisms underlying the unexplained in vivo activities of its inhibitors.

Escitalopram treatment for depressive disorder following acute coronary syndrome: a 24-week double-blind, placebo-controlled trial.

PubMed

Kim, Jae-Min; Bae, Kyung-Yeol; Stewart, Robert; Jung, Bo-Ok; Kang, Hee-Ju; Kim, Sung-Wan; Shin, Il-Seon; Hong, Young Joon; Kim, Ju Han; Shin, Hee-Young; Kang, Gaeun; Ahn, Youngkeun; Kim, Jong-Keun; Jeong, Myung Ho; Yoon, Jin-Sang

2015-01-01

Depression is common after acute coronary syndrome (ACS) and has adverse effects on prognosis. There are few evidence-based interventions for treating depression in ACS. This study investigated the efficacy and safety of escitalopram in treating depressive disorders identified 2-14 weeks after a confirmed ACS episode. A total of 217 patients with DSM-IV depressive disorders (121 major and 96 minor) and ACS were randomly assigned to receive escitalopram in flexible doses of 5-20 mg/d (n = 108) or placebo (n = 109) for 24 weeks. The study was conducted from 2007 to 2013. The primary outcome measure was the Hamilton Depression Rating Scale (HDRS). Secondary outcome measures included the Montgomery-Asberg Depression Rating Scale (MADRS), Beck Depression Inventory (BDI), Clinical Global Impressions-Severity of Illness scale (CGI-S), Social and Occupational Functioning Assessment Scale (SOFAS), and World Health Organization Disability Assessment Schedule-12. Cardiovascular safety outcomes included echocardiography, electrocardiography, laboratory test, body weight, and blood pressure results. Escitalopram was superior to placebo in reducing HDRS scores (mean difference = 2.3, P = .016, effect size = 0.38). Escitalopram was also superior to placebo in decreasing depressive symptoms evaluated by the MADRS, BDI, and CGI-S and in improving SOFAS functioning level. Escitalopram was not associated with any harmful changes in cardiovascular safety measures. Dizziness was significantly more frequently reported in the escitalopram group (P = .018), but there were no significant differences in any other adverse events. These results indicate that escitalopram has clinically meaningful antidepressant effects with no evidence of reduced cardiovascular safety in depressive disorder following ACS. ClinicalTrials.gov identifier: NCT00419471. © Copyright 2015 Physicians Postgraduate Press, Inc.

Comparison of escitalopram versus citalopram for the treatment of major depressive disorder in a geriatric population.

PubMed

Wu, Eric; Greenberg, Paul E; Yang, Elaine; Yu, Andrew; Erder, M Haim

2008-09-01

To compare escitalopram versus citalopram for the treatment of major depressive disorder (MDD) in geriatric patients. Administrative claims data (2003-2005) were analyzed for patients aged > or =65 years with at least one inpatient claim or two independent medical claims associated with MDD diagnosis. Patients were continuously enrolled for at least 12 months, filled at least one prescription for citalopram or escitalopram and had no second generation antidepressant use during the 6-month pre-index date. Contingency table analysis and survival analysis were used to compare outcomes between the two treatment groups. Treatment persistence, hospitalization utilization, and prescription drug, medical, and total healthcare costs were analyzed. Outcomes were compared between patients initiated on escitalopram and those initiated on citalopram both descriptively and using multivariate analysis adjusting for baseline characteristics. Among 691 geriatric patients, escitalopram-treated patients (n=459) were less likely to discontinue treatment (hazard ratio [HR]=0.83, p=0.049) or switch to another second generation antidepressant (HR=0.62, p=0.001) compared to patients treated with citalopram (n=232). Patients treated with escitalopram had a significantly lower hospitalization rate (31.2% vs. 38.8%, p=0.045) and 66% fewer hospitalization days based on negative binomial regression (p<0.001). While escitalopram patients had comparable prescription drug costs, they had lower total medical service costs (regression: $9748 vs. $19,208, p<0.001) and lower total healthcare costs (regression: $11,434 vs. $20,601, p<0.001). This study's limitations include its small sample size, short observational periods and exclusivity of indirect costs. Geriatric patients treated with escitalopram had better treatment persistence, fewer hospitalizations, and lower medical and total healthcare costs than patients treated with citalopram. Most of the cost reduction was attributable to significantly lower hospitalizations and total medical costs.

Efficacy and Tolerability of High-Dose Escitalopram in Posttraumatic Stress Disorder.

PubMed

Qi, Wei; Gevonden, Martin; Shalev, Arieh

2017-02-01

Open-label trials suggest that escitalopram (up to 20 mg/d) is an effective treatment for some, but not all posttraumatic stress disorder (PTSD) patients. Higher doses of escitalopram effectively reduced major depression symptoms in patients who had not responded to regular doses. The current study examines the efficacy, tolerability, and adherence to high-dose escitalopram in PTSD. Forty-five PTSD patients received 12 weeks of gradually increasing doses of escitalopram reaching 40 mg daily at 4 weeks. Among those, 12 participants received regular doses of antidepressants at study onset including escitalopram (n = 7). The Clinician-Administered PTSD Scale (CAPS) evaluated PTSD symptoms severity before treatment, at 3 months (upon treatment termination), and at 6 months (maintenance effect). A 20% reduction in CAPS scores was deemed clinically significant. Adverse events and medication adherence were monitored at each clinical session. Linear mixed-models analysis showed a significant reduction of mean CAPS scores (11.5 ± 18.1 points) at 3 months and maintenance of gains by 6 months (F2,34.56 = 8.15, P = 0.001). Eleven participants (34.3%) showed clinically significant improvement at 3 months. Only 9 participants (20%) left the study. There were no serious adverse events and few mild ones with only 2 adverse events (diarrhea, 11.1%; drowsiness, 11.1%) reported by more than 10% of participants. High doses of escitalopram are tolerable and well adhered to in PTSD. Their beneficial effect at a group level is due to a particularly good response in a subset of patients.Variability in prior pharmacological treatment precludes a definite attribution of the results to high doses of escitalopram.

A thorough QT study to evaluate the QTc prolongation potential of two neuropsychiatric drugs, quetiapine and escitalopram, in healthy volunteers.

PubMed

Kim, Anhye; Lim, Kyoung Soo; Lee, Howard; Chung, Hyewon; Yoon, Seo Hyun; Yu, Kyung-Sang; Cho, Joo-Youn; Jang, In-Jin; Chung, Jae-Yong

2016-07-01

Prolongation of the QT interval on an ECG is a surrogate marker for predicting the proarrhythmic potential of a drug under development. The aim of this study was to evaluate the QTc prolongation potential of two neuropsychiatric drugs, quetiapine immediate release (IR) and escitalopram, in healthy individuals. This was a randomized, open-label, 4×4 Williams crossover study, with four single-dose treatments [placebo, 400 mg moxifloxacin (positive control), 20 mg escitalopram, and 100 mg quetiapine IR], conducted in 40 healthy volunteers. Serial blood samples for pharmacokinetics and ECG were collected. Individually, RR-corrected QTc intervals (QTcI) and placebo-adjusted changes from baseline values of QTcI (ΔΔQTcI) were evaluated. Lower-bound values of the one-sided 95% confidence interval for ΔΔQTcI of moxifloxacin with more than 5 ms confirmed the sensitivity of the assay. The maximum upper bound 95% confidence interval for the ΔΔQTcI of quetiapine IR and escitalopram was 13.7 and 10.5 ms, with mean estimates of 10.2 and 6.9 ms, respectively. Peak effects of moxifloxacin and quetiapine IR on ΔΔQTcI were observed at approximately time to maximum concentration (Tmax), whereas that of escitalopram was observed 3 h after Tmax. The concentration-ΔΔQTcI relationships of quetiapine IR and escitalopram were relatively flat, as compared with that of moxifloxacin. The results demonstrated the validity of trial methodology and that quetiapine IR and escitalopram caused QT prolongation in healthy individuals. In addition, hysteresis of escitalopram-induced QTc prolongation. These results indicate that higher doses of these drugs could lead to greater QT prolongation in a dose-response manner.

The Role of the Two-Pore Domain Potassium Channel TREK-1 in the Therapeutic Effects of Escitalopram in a Rat Model of Poststroke Depression.

PubMed

Lin, Dai-Hua; Zhang, Xiang-Rong; Ye, Dong-Qing; Xi, Guang-Jun; Hui, Jiao-Jie; Liu, Shan-Shan; Li, Lin-Jiang; Zhang, Zhi-Jun

2015-06-01

Poststroke depression (PSD) is one of the most common neuropsychiatric complications after stroke. TREK-1, a two-pore-domain potassium channel, has been implicated in the pathogenesis of stroke and depression. The aim of this study was to investigate whether TREK-1 plays a role in the therapeutic effects of the selective serotonin reuptake inhibitor (SSRI) escitalopram in a rat PSD model. The whole-cell patch-clamp technique was performed to assess the effect of escitalopram on recombinant TREK-1 currents in HEK293 cells. The expression of TREK-1 mRNA and protein was measured in the hippocampus and prefrontal cortex (PFC), and neural stem cell (NSC) proliferation was detected in the hippocampal dentate gyrus (DG) in PSD rats after 3 weeks of escitalopram administration. Escitalopram reversibly inhibited TREK-1 currents in a concentration-dependent manner. Chronic treatment with escitalopram significantly reversed the reductions in weight gain, locomotor activity, and sucrose preference in PSD rats. The expressions of TREK-1 mRNA and protein were significantly increased in hippocampal CA1, CA3, DG, and PFC in PSD rats, with the exception of TREK-1 mRNA in hippocampal CA1. NSC proliferation was significantly decreased in hippocampal DG of PSD rats. Escitalopram significantly reversed the regional increases of TREK-1 expression and the reduction of hippocampal NSC proliferation in PSD rats. TREK-1 plays an important role in the therapeutic effects of the SSRI escitalopram in PSD model, making TREK-1 an attractive candidate molecule for further understanding the pathophysiology and treatment of PSD. © 2015 John Wiley & Sons Ltd.

Health Canada Warning on Citalopram and Escitalopram--Its Effects on Prescribing in Consultation-Liaison Psychiatry.

PubMed

Do, André; Noohi, Saeid; Elie, Dominique; Mahdanian, Artin A; Yu, Ching; Segal, Marilyn; Looper, Karl J; Rej, Soham

2016-01-01

Reports have suggested that citalopram and escitalopram may prolong the QTc interval, leading Health Canada to issue a warning to limit their dosages in 2012. Little is known about the effects of this warning and similar ones (e.g., by the Food and Drug Administration) on antidepressant prescribing in inpatients with acute medical illness, who are theoretically at high risk of QTc prolongation. The main objective of our study is to examine the effect of the Health Canada warning on citalopram/escitalopram prescribing patterns in the consultation-liaison (C-L) psychiatry setting. We performed a retrospective cohort study including 275 randomly selected inpatients with medical illness assessed by the psychiatric C-L team of a large Canadian academic hospital between 2008 and 2014. We grouped patients based on whether they were assessed by the C-L team before or after the citalopram Health Canada warning. Our primary outcome was change in citalopram/escitalopram prescribing patterns. We found that of patients seen before the Health Canada warning, a significantly higher number were prescribed citalopram/escitalopram (44.1% vs. 22.3%, χ(2) = 14.835, p < 0.001), even after controlling for confounders. However, the percentage of patients using a citalopram/escitalopram dose exceeding those recommended by the Health Canada warning was similar in both groups (8.9% vs. 12.1%, χ(2) = 0.233, p = 0.63). Overall, C-L psychiatrists were less likely to prescribe citalopram/escitalopram following the Health Canada warning, which did not translate into safer dosing. Clinicians should not avoid prescribing citalopram/escitalopram appropriately in medically vulnerable inpatients when benefits outweigh disadvantages. Copyright © 2016 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

An Open-Label Trial of Escitalopram in Pervasive Developmental Disorders.

ERIC Educational Resources Information Center

Owley, Thomas; Walton, Laura; Salt, Jeff; Guter, Stephen J., Jr.; Winnega, Marrea; Leventhal, Bennett L.; Cook, Edwin H., Jr.

2005-01-01

Objective: To assess the effect of escitalopram in the treatment of pervasive developmental disorders (PDDs). Method: This 10-week study had a forced titration, open-label design. Twenty-eight subjects (mean age 125.1 [+ or -] 33.5 months) with a PDD received escitalopram at a dose that increased weekly to a maximum dose of 20 mg as tolerated. The…

Improving depression and enhancing resilience in family dementia caregivers: a pilot randomized placebo-controlled trial of escitalopram.

PubMed

Lavretsky, Helen; Siddarth, Prabha; Irwin, Michael R

2010-02-01

This study examined the potential of an antidepressant drug, escitalopram, to improve depression, resilience to stress, and quality of life in family dementia caregivers in a randomized placebo-controlled double-blinded trial. Forty family caregivers (43-91 years of age, 25 children and 15 spouses; 26 women) who were taking care of their relatives with Alzheimer disease were randomized to receive either escitalopram 10 mg/day or placebo for 12 weeks. Severity of depression, resilience, burden, distress, quality of life, and severity of care-recipient's cognitive and behavioral disturbances were assessed at baseline and over the course of the study. The Hamilton Depression Rating Scale scores at baseline ranged between 10 and 28. The groups were stratified by the diagnosis of major and minor depression. Most outcomes favored escitalopram over placebo. The severity of depression improved, and the remission rate was greater with the drug compared with placebo. Measures of anxiety, resilience, burden, and distress improved on escitalopram compared with placebo. Among caregivers, this small randomized controlled trial found that escitalopram use resulted in improvement in depression, resilience, burden and distress, and quality of life. Our results need to be confirmed in a larger sample.

Comparing treatment persistence, healthcare resource utilization, and costs in adult patients with major depressive disorder treated with escitalopram or citalopram.

PubMed

Wu, Eric Q; Greenberg, Paul E; Ben-Hamadi, Rym; Yu, Andrew P; Yang, Elaine H; Erder, M Haim

2011-03-01

Major depressive disorder is the most common type of depression, affecting 6.6% of adults in the United States annually. Citalopram and escitalopram are common second-generation antidepressants used for the treatment of patients with this disorder. Because citalopram is available in generic forms that have lower acquisition costs compared with the branded escitalopram, some health plans may provide incentives to encourage the use of the generic option. Decisions based solely on drug acquisition costs may encourage the use of a therapy that is less cost-effective when treatment persistence, healthcare utilization, and overall costs are factored in. To compare, in a real-world setting, the treatment persistence, healthcare utilization, and overall costs of managing adult patients with major depressive disorder who are treated with escitalopram or citalopram. Administrative claims data (from January 1, 2003, to June 30, 2005) were analyzed for patients with major depressive disorder aged ≥18 years. Patients filled ≥1 prescriptions for citalopram or for escitalopram (first-fill time was defined as the index date) and had no second-generation antidepressant use during the 6-month preindex period. Treatment persistence, healthcare utilization, and healthcare costs were measured over the 6-month preindex and 6-month postindex periods and compared between patients treated with citalopram or escitalopram, using unadjusted and multivariate analyses. Patients receiving escitalopram (N = 10,465) were less likely to discontinue the treatment (hazard ratio 0.94; P = .005) and switch to another second-generation antidepressant (hazard ratio 0.83; P <.001) than patients receiving citalopram (N = 4212). Patients receiving escitalopram were also less likely to have a hospital admission (odds ratio 0.88; P = .036) or an emergency department visit and had lower total healthcare costs (-$1174) and major depressive disorder-related costs (-$109; P <.001) during the study period. Although the drug acquisition costs are lower for generic citalopram than for the brand-name escitalopram, patients treated with escitalopram had better treatment persistence, lower healthcare utilization, and lower overall costs compared with patients treated with citalopram over the study period. This may suggest that other considerations, in addition to acquisition cost, may need to be factored in to assess the cost-effectiveness of drug therapy.

Comparing Treatment Persistence, Healthcare Resource Utilization, and Costs in Adult Patients with Major Depressive Disorder Treated with Escitalopram or Citalopram

PubMed Central

Wu, Eric Q.; Greenberg, Paul E.; Ben-Hamadi, Rym; Yu, Andrew P.; Yang, Elaine H.; Erder, M. Haim

2011-01-01

Background Major depressive disorder is the most common type of depression, affecting 6.6% of adults in the United States annually. Citalopram and escitalopram are common second-generation antidepressants used for the treatment of patients with this disorder. Because citalopram is available in generic forms that have lower acquisition costs compared with the branded escitalopram, some health plans may provide incentives to encourage the use of the generic option. Decisions based solely on drug acquisition costs may encourage the use of a therapy that is less cost-effective when treatment persistence, healthcare utilization, and overall costs are factored in. Objective To compare, in a real-world setting, the treatment persistence, healthcare utilization, and overall costs of managing adult patients with major depressive disorder who are treated with escitalopram or citalopram. Methods Administrative claims data (from January 1, 2003, to June 30, 2005) were analyzed for patients with major depressive disorder aged ≥18 years. Patients filled ≥1 prescriptions for citalopram or for escitalopram (first-fill time was defined as the index date) and had no second-generation antidepressant use during the 6-month preindex period. Treatment persistence, healthcare utilization, and healthcare costs were measured over the 6-month preindex and 6-month postindex periods and compared between patients treated with citalopram or escitalopram, using unadjusted and multivariate analyses. Results Patients receiving escitalopram (N = 10,465) were less likely to discontinue the treatment (hazard ratio 0.94; P = .005) and switch to another second-generation antidepressant (hazard ratio 0.83; P <.001) than patients receiving citalopram (N = 4212). Patients receiving escitalopram were also less likely to have a hospital admission (odds ratio 0.88; P = .036) or an emergency department visit and had lower total healthcare costs (−$1174) and major depressive disorder–related costs (−$109; P <.001) during the study period. Conclusion Although the drug acquisition costs are lower for generic citalopram than for the brand-name escitalopram, patients treated with escitalopram had better treatment persistence, lower healthcare utilization, and lower overall costs compared with patients treated with citalopram over the study period. This may suggest that other considerations, in addition to acquisition cost, may need to be factored in to assess the cost-effectiveness of drug therapy. PMID:25126340

Citalopram and escitalopram in the treatment of major depressive disorder: a pooled analysis of 3 clinical trials.

PubMed

Li, Huafang; Li, Ting; Li, Guanjun; Luo, Jianfeng

2014-11-01

Pooled analysis is a powerful technique that is increasingly used to detect differences in efficacy between pharmacologic agents. Some studies have compared the efficacy and tolerability of citalopram and escitalopram, with contradictory results. The aim of this study was to compare the efficacy and tolerability of citalopram and escitalopram in the treatment of major depressive disorder (MDD) using pooled analyses. Data from 3 randomized, double-blind studies that compared citalopram (20 to 40 mg/d) and escitalopram (10 to 20 mg/d) were pooled and analyzed. The primary efficacy parameter was change from baseline in the 17-item Hamilton Rating Scale for Depression (HAM-D-17) total score. Efficacy assessments were made at weeks 0 (baseline), 1, 2, 4, and 6. Based on the mean change from baseline in the HAM-D-17 at weeks 1, 2, 4, and 6, the efficacy of citalopram, 20 to 40 mg/d, was equivalent to escitalopram, 10 to 20 mg/d (P > .05). Similar results were seen for severely depressed patients, with a mean treatment difference of 13.9 (SE = 7.6) vs 15.9 (SE = 7.5). Response and remission rates at week 6 were similar (response, 72.4% for citalopram, compared with 73.5% for escitalopram; remission, 52.6% vs 54.5%, respectively). The pooled analysis showed that over a 6-week treatment period, citalopram, 20 to 40 mg/d, is equivalent to escitalopram, 10 to 20 mg/d, in both efficacy and tolerability.

Effect of proton pump inhibitors on the serum concentrations of the selective serotonin reuptake inhibitors citalopram, escitalopram, and sertraline.

PubMed

Gjestad, Caroline; Westin, Andreas A; Skogvoll, Eirik; Spigset, Olav

2015-02-01

The selective serotonin reuptake inhibitors (SSRIs) citalopram, escitalopram, and sertraline are all metabolized by the cytochrome P-450 isoenzyme CYP2C19, which is inhibited by the proton pump inhibitors (PPIs) omeprazole, esomeprazole, lansoprazole, and pantoprazole. The aim of the present study was to evaluate the effect of these PPIs on the serum concentrations of citalopram, escitalopram, and sertraline. Serum concentrations from patients treated with citalopram, escitalopram, or sertraline were obtained from a routine therapeutic drug monitoring database, and samples from subjects concomitantly using PPIs were identified. Dose-adjusted SSRI serum concentrations were calculated to compare data from those treated and those not treated with PPIs. Citalopram concentrations were significantly higher in patients treated with omeprazole (+35.3%; P < 0.001), esomeprazole (+32.8%; P < 0.001), and lansoprazole (+14.7%; P = 0.043). Escitalopram concentrations were significantly higher in patients treated with omeprazole (+93.9%; P < 0.001), esomeprazole (+81.8%; P < 0.001), lansoprazole (+20.1%; P = 0.008), and pantoprazole (+21.6%; P = 0.002). Sertraline concentrations were significantly higher in patients treated with esomeprazole (+38.5%; P = 0.0014). The effect of comedication with PPIs on the serum concentration of SSRIs is more pronounced for omeprazole and esomeprazole than for lansoprazole and pantoprazole, and escitalopram is affected to a greater extent than are citalopram and sertraline. When omeprazole or esomeprazole are used in combination with escitalopram, a 50% dose reduction of the latter should be considered.

Escitalopram versus placebo in the treatment of dysthymic disorder.

PubMed

Hellerstein, David J; Batchelder, Sarai T; Hyler, Steven; Arnaout, Bachaar; Toba, Christina; Benga, Ileana; Gangure, Dinu

2010-05-01

Numerous studies have assessed the acute efficacy of antidepressants, including selective serotonin reuptake inhibitors, in treating dysthymic disorder; however, escitalopram, the S-enantiomer of citalopram, has not been studied. Thirty-six outpatients with Structured Clinical Interview for DSM-III-R-diagnosed dysthymic disorder, aged 23-65 years (mean±SD=44.7±11 years), were randomly assigned to double-blind escitalopram (maximum dose 20 mg/day) versus placebo for 12 weeks. Inclusion criteria included age 18-65 years and Hamilton Depression Rating Scale (HDRS) score≥12. We hypothesized that escitalopram would be superior to placebo in the HDRS-24 item total score at week 12. We also hypothesized the superiority of escitalopram over placebo for secondary measures, including the percentage of participants classified as responders and remitters, as well as social functioning (Social Adjustment Scale), clinical global impression-improvement, Global Assessment of Functioning Scale. Participants' baseline HDRS-24 averaged 23.4±5.9. Final HDRS-24 scores at last observation carried forward did not differ significantly between escitalopram-treated (mean±SD=10.88±5.83) and placebo-treated individuals (mean±SD=16.4±6.34) (F=2.82, degrees of freedom=1,32, P=0.10). Significant differences favoring active medication were found on the Social Adjustment Scale and the Clinical Global Impression Severity and Global Assessment of Functioning Scale, but not in the percentages of responders or remitters. A larger study sample or higher escitalopram dose may show more significant placebo-medication differences.

Safety of escitalopram in pregnancy: a case series.

PubMed

Bellantuono, Cesario; Bozzi, Francesca; Orsolini, Laura

2013-01-01

The aim of this paper is to report maternal and neonatal outcomes in pregnant women treated with escitalopram during pregnancy and breastfeeding. Women enrolled in the DEGRA Database at the Clinic of Affective Disorders in Pregnancy and Postpartum in Italy, treated during pregnancy with escitalopram and followed up throughout pregnancy, were included in this study. All patients provided written informed consent and the study was approved by the local ethics committee. Psychiatric diagnoses were assessed using the Structured Clinical Interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition) Axis I Disorders and symptoms were assessed using the Hamilton Rating Scale for Depression (17 items) and Hamilton Rating Scale for Anxiety (14 items). Clinical and sociodemographic characteristics as well as maternal and neonatal outcomes were recorded. The case histories of seven pregnant women treated for depression and/or anxiety disorders with escitalopram were reported. Four women were also treated with benzodiazepines. All pregnancies were full-term and all newborns had normal Apgar scores. There were no major malformations or miscarriages following exposure to escitalopram. Mild withdrawal syndrome was reported only in a newborn who was also exposed to a benzodiazepine. Two infants exposed to escitalopram during breastfeeding did not show any health problems. Our experience with use of escitalopram in pregnant women did not reveal any maternal or neonatal concerns. However, considering the few cases analyzed and the paucity of published literature, no conclusions can be drawn on its safety profile in pregnancy and breastfeeding.

Safety of escitalopram in pregnancy: a case series

PubMed Central

Bellantuono, Cesario; Bozzi, Francesca; Orsolini, Laura

2013-01-01

Background The aim of this paper is to report maternal and neonatal outcomes in pregnant women treated with escitalopram during pregnancy and breastfeeding. Methods Women enrolled in the DEGRA Database at the Clinic of Affective Disorders in Pregnancy and Postpartum in Italy, treated during pregnancy with escitalopram and followed up throughout pregnancy, were included in this study. All patients provided written informed consent and the study was approved by the local ethics committee. Psychiatric diagnoses were assessed using the Structured Clinical Interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition) Axis I Disorders and symptoms were assessed using the Hamilton Rating Scale for Depression (17 items) and Hamilton Rating Scale for Anxiety (14 items). Clinical and sociodemographic characteristics as well as maternal and neonatal outcomes were recorded. Results The case histories of seven pregnant women treated for depression and/or anxiety disorders with escitalopram were reported. Four women were also treated with benzodiazepines. All pregnancies were full-term and all newborns had normal Apgar scores. There were no major malformations or miscarriages following exposure to escitalopram. Mild withdrawal syndrome was reported only in a newborn who was also exposed to a benzodiazepine. Two infants exposed to escitalopram during breastfeeding did not show any health problems. Conclusion Our experience with use of escitalopram in pregnant women did not reveal any maternal or neonatal concerns. However, considering the few cases analyzed and the paucity of published literature, no conclusions can be drawn on its safety profile in pregnancy and breastfeeding. PMID:24043940

The antidepressant- and anxiolytic-like effects following co-treatment with escitalopram and risperidone in rats.

PubMed

Kaminska, K; Rogoz, Z

2016-06-01

Several clinical reports have documented a beneficial effect of the addition of a low dose of risperidone to the ongoing treatment with antidepressants, in particular selective serotonin reuptake inhibitors (SSRI), in the treatment of drug-resistant depression and treatment-resistant anxiety disorders. In the present study, we investigated the effect of treatment with the antidepressant escitalopram (SSRI) given separately or jointly with a low dose of risperidone (an atypical antipsychotic) in the forced swim test and in the elevated plus-maze test in rats. The obtained results showed that escitalopram at doses of 2.5 or 5 mg/kg evoked antidepressant-like effect in the forced swim test. Moreover, risperidone at low doses (0.05 or 0.1 mg/kg) enhanced the antidepressant-like activity of escitalopram (1 mg/kg) in this test by increasing the swimming time and decreasing the immobility time in those animals. WAY 100635 (a serotonin 5-HT1A receptor antagonist) at a dose of 0.1 mg/kg abolished the antidepressant-like effect induced by co-administration of escitalopram and risperidone. The active behavior in that test did not reflect an increase in general activity, since the combined treatment with escitalopram and risperidone failed to enhance the exploratory activity of rats. In the following experiment, we showed that escitalopram (5 mg/kg) and mirtazapine (5 or 10 mg/kg) or risperidone (0.1 mg/kg) induced an anxiolytic-like effect in the elevated plus-maze test, and the combined treatment with an ineffective dose of risperidone (0.05 mg/kg) enhanced the anxiolytic-like effects of escitalopram (2.5 mg/kg) or mirtazapine (1 and 2.5 mg/kg) in this test. The obtained results suggest that risperidone applied at a low dose enhances the antidepressant-like activity of escitalopram in the forced swim test, and that 5-HT1A receptors may play some role in these effects. Moreover, a low dose of risperidone may also enhance the anxiolytic-like action of the studied antidepressants.

Single i.v. ketamine augmentation of newly initiated escitalopram for major depression: results from a randomized, placebo-controlled 4-week study.

PubMed

Hu, Y-D; Xiang, Y-T; Fang, J-X; Zu, S; Sha, S; Shi, H; Ungvari, G S; Correll, C U; Chiu, H F K; Xue, Y; Tian, T-F; Wu, A-S; Ma, X; Wang, G

2016-02-01

While oral antidepressants reach efficacy after weeks, single-dose intravenous (i.v.) ketamine has rapid, yet time-limited antidepressant effects. We aimed to determine the efficacy and safety of single-dose i.v. ketamine augmentation of escitalopram in major depressive disorder (MDD). Thirty outpatients with severe MDD (17-item Hamilton Rating Scale for Depression total score ⩾ 24) were randomized to 4 weeks double-blind treatment with escitalopram 10 mg/day+single-dose i.v. ketamine (0.5 mg/kg over 40 min) or escitalopram 10 mg/day + placebo (0.9% i.v. saline). Depressive symptoms were measured using the Montgomery-Asberg Depression Rating Scale (MADRS) and the Quick Inventory of Depressive Symptomatology - Self-Report (QIDS-SR). Suicidal ideation was evaluated with the QIDS-SR item 12. Adverse psychopathological effects were measured with the Brief Psychiatric Rating Scale (BPRS)-positive symptoms, Young Mania Rating Scale (YMRS) and Clinician Administered Dissociative States Scale (CADSS). Patients were assessed at baseline, 1, 2, 4, 24 and 72 h and 7, 14, 21 and 28 days. Time to response (⩾ 50% MADRS score reduction) was the primary outcome. By 4 weeks, more escitalopram + ketamine-treated than escitalopram + placebo-treated patients responded (92.3% v. 57.1%, p = 0.04) and remitted (76.9% v. 14.3%, p = 0.001), with significantly shorter time to response [hazard ratio (HR) 0.04, 95% confidence interval (CI) 0.01-0.22, p < 0.001] and remission (HR 0.11, 95% CI 0.02-0.63, p = 0.01). Compared to escitalopram + placebo, escitalopram + ketamine was associated with significantly lower MADRS scores from 2 h to 2 weeks [(peak = 3 days-2 weeks; effect size (ES) = 1.08-1.18)], QIDS-SR scores from 2 h to 2 weeks (maximum ES = 1.27), and QIDS-SR suicidality from 2 to 72 h (maximum ES = 2.24). Only YMRS scores increased significantly with ketamine augmentation (1 and 2 h), without significant BPRS or CADSS elevation. Single-dose i.v. ketamine augmentation of escitalopram was safe and effective in severe MDD, holding promise for speeding up early oral antidepressant efficacy.

[Escitalopram and citalopram: the unexpected role of the R-enantiomer].

PubMed

Jacquot, C; David, D J; Gardier, A M; Sánchez, C

2007-01-01

Citalopram, a selective serotonin reuptake inhibitor, is composed of 2 enantiomers, R-citalopram and S-citalopram, 2 different non-superimposable mirror image forms of the same molecule. Separating these 2 enantiomers has enabled studying their individual properties. Citalopram's pharmacologic activity is centered on the S enantiomer's high affinity for the serotonin transporter which is twice as high as citalopram's and 30 to 40 times higher than R-citalopram. This leads to an inhibition of serotonin reuptake two times higher for escitalopram compared with citalopram and confirms that citalopram's pharmacologic activity is due to the S-enantiomer. Contrary to what might be expected, the effect of escitalopram (DCI of S-citalopram) is not superimposable on an equivalent dose of citalopram but is superior. Several hypotheses could explain this superiority. First, conversions of the S-enantiomer into the R-enantiomer may occur, but there is no reason why this phenomenon would happen more when both enantiomers are present than when escitalopram is alone. Furthermore, pharmacokinetic studies have shown that S or R configurations are stable in vivo. Second, a particular action of R-citalopram may influence the S-enantiomer's kinetic from intestinal absorption to blood-brain barrier. But concentrations of both enantiomers in the frontal cortex are the same. Therefore, R-citalopram does not interfere with escitalopram's kinetic. Finally, interactions may appear at the synaptic level. Results of experimentation, after in situ injection to the cortex level, confirm that an interaction between the 2 enantiomers takes place at that level. A direct negative interaction of R-citalopram on one or several effectors that create the antidepressive effect seems justified. This negative interaction has been studied in depth. Animal models have shown that the R-enantiomer has no antidepressive potential and when associated with escitalopram prohedonic effects disappear. Escitalopram is more powerful than citalopram in reducing anxiety but the presence of R-citalopram reduces the positive effects of escitalopram. We then may conclude that R-citalopram antagonizes the antidepressive effects of escitalopram and that its presence limits the therapeutic effect and reduces the speed of action of citalopram. The antagonism of escitalopram by R-citalopram was not expected and one hypothesis is that a direct interaction between the 2 enantiomers may occur on a particular site of the serotonin transporter. Results have shown that R-citalopram has a significant affinity only for the allosteric site of the transporter, which regulates the affinity of the ligand for the active site at the origin of serotonin reuptake inhibition. Unlike citalopram, escitalopram's pharmacologic action is not blocked by R-citalopram explaining its greater therapeutic efficacy and more rapid mode of action.

In vivo imaging of serotonin transporter occupancy by means of SPECT and [123I]ADAM in healthy subjects administered different doses of escitalopram or citalopram.

PubMed

Klein, N; Sacher, J; Geiss-Granadia, T; Attarbaschi, T; Mossaheb, N; Lanzenberger, R; Pötzi, C; Holik, A; Spindelegger, C; Asenbaum, S; Dudczak, R; Tauscher, J; Kasper, S

2006-10-01

Escitalopram is a dual serotonin reuptake inhibitor (SSRI) approved for the treatment of depression and anxiety disorders. It is the S-enantiomer of citalopram, and is responsible for the serotonin reuptake activity, and thus for its pharmacological effects. Previous studies pointed out that clinically efficacious doses of other SSRIs produce an occupancy of the serotonin reuptake transporter (SERT) of about 80% or more. The novel radioligand [123I]ADAM and single photon emission computer tomography (SPECT) were used to measure midbrain SERT occupancies for different doses of escitalopram and citalopram. Twenty-five healthy subjects received a single dose of escitalopram [5 mg (n=5), 10 mg (n=5), and 20 mg (n=5)] or citalopram [(10 mg (n=5) and 20 mg (n=5)]. Midbrain SERT binding was measured with [(123)I]ADAM and SPECT on two study days, once without study drug and once 6 h after single dose administration of the study drug. The ratio of midbrain-cerebellum/cerebellum was the outcome measure (V3") for specific binding to SERT in midbrain. Subsequently, SERT occupancy levels were calculated using the untreated baseline level for each subject. An Emax model was used to describe the relationship between S-citalopram concentrations and SERT occupancy values. Additionally, four subjects received placebo to determine test-retest variability. Single doses of 5, 10, or 20 mg escitalopram led to a mean SERT occupancy of 60+/-6, 64+/-6, and 75+/-5%, respectively. SERT occupancies for subjects treated with single doses of 10 and 20 mg citalopram were 65+/-10 and 70+/-6%, respectively. A statistically significant difference was found between SERT occupancies after application of 10 and 20 mg escitalopram, but not for 10 and 20 mg citalopram. There was no statistically significant difference between the SERT occupancies of either 10 mg citalopram or 10 mg escitalopram, or between 20 mg citalopram and 20 mg escitalopram. Emax was slightly higher after administration of citalopram (84%) than escitalopram (79%). In the test-retest study, a mean SERT "occupancy" of 4% was found after administration of placebo, the intraclass correlation coefficient was 0.92, and the repeatability coefficient was 0.25. SPECT and [123I]ADAM were used to investigate SERT occupancies after single doses of escitalopram or citalopram. The test-retest study revealed good reproducibility of SERT quantification. Similar SERT occupancies were found after administration of equal doses (in respect to mg) of escitalopram and citalopram, giving indirect evidence for a fractional blockade of SERT by the inactive R-citalopram.

Improving depression and enhancing resilience in family dementia caregivers: a pilot randomized placebo-controlled trial of escitalopram

PubMed Central

Lavretsky, H.; Siddarth, P.; Irwin, M. R.

2009-01-01

Background This study examined the potential of an antidepressant drug, escitalopram, to improve depression, resilience to stress, and quality of life in family dementia caregivers in a randomized placebo-controlled double-blind trial. Methods Forty family caregivers (43–91 years of age, 25 children and 15 spouses; 26 women) who were taking care of their relatives with Alzheimer’s disease were randomized to receive either escitalopram 10 mg/day or placebo for 12 weeks. Severity of depression, resilience, burden, distress, quality of life, and severity of care-recipient’s cognitive and behavioral disturbances were assessed at baseline and over the course of the study. The Hamilton Depression Rating Scale (HDRS) scores at baseline ranged between 10–28. The groups were stratified by the diagnosis of major and minor depression. Results Most outcomes favored escitalopram over placebo. The severity of depression improved and the remission rate was greater with the drug compared to placebo. Measures of anxiety, resilience, burden and distress improved on escitalopram compared to placebo. Discussion Among caregivers, this small randomized controlled trial found that escitalopram use resulted in improvement in depression, resilience, burden and distress, and quality of life. Our results need to be confirmed in a larger sample. PMID:20104071

Escitalopram Ameliorates Forskolin-Induced Tau Hyperphosphorylation in HEK239/tau441 Cells.

PubMed

Ren, Qing-Guo; Wang, Yan-Juan; Gong, Wei-Gang; Zhou, Qi-Da; Xu, Lin; Zhang, Zhi-Jun

2015-06-01

To investigate the effect of escitalopram (a widely used and highly efficacious antidepressant from the SSRI class) on tau hyperphosphorylation, HEK293/tau441 cells were pretreated with 4 μM of forskolin for 2 h. Then we treated the cells with different doses of escitalopram (0, 5, 10, 20, 40, 80 μM) for 22 h. We measured the phosphorylation level of tau by Western blotting. It was shown that escitalopram could protect tau from hyperphosphorylation induced by pharmacological activation of protein kinase A (PKA) at a dose of 20, 40, and 80 μM in vitro. Interestingly, the same dose of escitalopram could also increase the level of serine-9-phosphorylated GSK-3β (inactive form) and the phosphorylation level of Akt at Ser473 (active form) with no significant change in the level of total GSK-3β and Akt. Unexpectedly, 5-hydroxytryptamine 1A receptor (5-HT1A) agonist 8-OH-DPAT did not decrease forskolin-induced tau hyperphosphorylation. Our results suggest that escitalopram can ameliorate forskolin-induced tau hyperphosphorylation, which is not through the typical 5-HT1A pathway, and Akt/GSK-3β signaling pathway is involved. These findings may support an effective role of antidepressants in the prevention of dementia associated with depression in patients.

Escitalopram—translating molecular properties into clinical benefit: reviewing the evidence in major depression

PubMed Central

Leonard, Brian; Taylor, David

2010-01-01

The majority of currently marketed drugs contain a mixture of enantiomers; however, recent evidence suggests that individual enantiomers can have pharmacological properties that differ importantly from enantiomer mixtures. Escitalopram, the S-enantiomer of citalopram, displays markedly different pharmacological activity to the R-enantiomer. This review aims to evaluate whether these differences confer any significant clinical advantage for escitalopram over either citalopram or other frequently used antidepressants. Searches were conducted using PubMed and EMBASE (up to January 2009). Abstracts of the retrieved studies were reviewed independently by both authors for inclusion. Only those studies relating to depression or major depressive disorder were included. The search identified over 250 citations, of which 21 studies and 18 pooled or meta-analyses studies were deemed suitable for inclusion. These studies reveal that escitalopram has some efficacy advantage over citalopram and paroxetine, but no consistent advantage over other selective serotonin reuptake inhibitors. Escitalopram has at least comparable efficacy to available serotonin-norepinephrine reuptake inhibitors, venlafaxine XR and duloxetine, and may offer some tolerability advantages over these agents. This review suggests that the mechanistic advantages of escitalopram over citalopram translate into clinical efficacy advantages. Escitalopram may have a favourable benefit-risk ratio compared with citalopram and possibly with several other antidepressant agents. PMID:20147575

Combined therapy versus usual care for the treatment of depression in oncologic patients: a randomized controlled trial.

PubMed

Rodríguez Vega, B; Palao, A; Torres, G; Hospital, A; Benito, G; Pérez, E; Dieguez, M; Castelo, B; Bayón, C

2011-09-01

To compare narrative therapy (NT) plus escitalopram versus escitalopram plus usual care on quality of life and depressive symptomatology of depressed patients with oncologic disease. A total of 72 subjects (mean age 54.6 years), predominantly female with non-metastatic breast, lung and colon cancer and depressive disorder (DSM-IV-TR) were randomized to receive treatment with NT plus escitalopram (n=39) or escitalopram (10-20 mg QD) plus usual care (n=33). Main endpoints were improvement in dimensions of quality of life measured by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C-30 and reduction of depressive symptoms using the Hospital Anxiety and Depression Scale at weeks 12 and 24. The combined therapy group showed significantly greater improvement in all the functioning dimensions (p<0.01), pain scale (p=0.02), global health (p=0.02), and global quality of life (p=0.007) at weeks 12 and 24. There were no statistically significant differences in depressive symptomatology between the groups. From week 12 to week 24 study retention was higher in the combined treatment group (p=0.01). Brief NT in combination with escitalopram was superior to usual care and escitalopram in improving functioning dimensions of quality life. Copyright © 2010 John Wiley & Sons, Ltd.

Selective verbal and spatial memory impairment after 5-HT1A and 5-HT2A receptor blockade in healthy volunteers pre-treated with an SSRI.

PubMed

Wingen, M; Kuypers, K P C; Ramaekers, J G

2007-07-01

Serotonergic neurotransmission has been implicated in memory impairment. It is unclear however if memory performance is mediated through general 5-HT availability, through specific 5-HT receptors or both. The aim of the present study was to assess the contribution of 5-HT reuptake inhibition and specific blockade of 5-HT(1A) and 5-HT(2A) receptors to memory impairment. The study was conducted according to a randomized, double-blind, placebo-controlled, four-way cross-over design including 16 healthy volunteers. The treatment consisted of oral administration of escitalopram 20 mg + placebo, escitalopram 20 mg + ketanserin 50 mg, escitalopram 20 mg + pindolol 10 mg and placebo on 4 separate days with a washout period of minimum 7 days. Different memory tasks were performed including verbal memory, spatial working memory and reversal learning. Escitalopram showed an impairing effect on immediate verbal recall which nearly reached statistical significance. No effects of escitalopram were found on other types of memory. In combination with pindolol, immediate verbal recall was significantly impaired. Escitalopram in combination with ketanserin impaired spatial working memory significantly. No effects were found on reversal learning. Selective impairment of immediate verbal recall after a 5-HT(1A) partial agonist and selective impairment of spatial working memory performance after 5-HT(2A) receptor antagonist, both in combination with a selective serotonergic reuptake inhibitor (escitalopram), suggests that 5-HT(1A) and 5-HT(2A) receptors are distinctly involved in verbal and spatial memory.

Escitalopram is Associated with Reductions in Pain Severity and Pain Interference in Opioid Dependent Patients with Depressive Symptoms

PubMed Central

Tsui, Judith I.; Herman, Debra S.; Kettavong, Malyna; Anderson, Bradley J.; Stein, Michael D.

2011-01-01

Pain is common among opioid dependent patients, yet pharmacologic strategies are limited. The aim of this study was to explore whether escitalopram, a selective serotonin reuptake inhibitor, was associated with reductions in pain. The study used longitudinal data from a randomized, controlled trial that evaluated the effects of escitalopram on treatment retention in patients with depressive symptoms who were initiating buprenorphine/naloxone for treatment of opioid dependence. Participants were randomized to take escitalopram 10mg or placebo daily. Changes in pain severity, pain interference and depression were assessed at 1, 2 and 3 months visits using the Visual Analog Scale, Brief Pain Inventory and the Beck Depression Inventory II, respectively. Fixed-effects estimator for panel regression models were used to assess the effects of intervention on changes in outcomes over time. Additional models were estimated to explore whether the intervention effect was mediated by within-person changes in depression. In this sample of 147 adults, we found that participants randomized to escitalopram had significantly larger reductions on both pain severity (b = −14.34, t = −2.66, p < .01) and pain interference (b = −1.20, t = −2.23, p < .05) between baseline and follow-up. After adjusting for within-subject changes in depression, the estimated effects of escitalopram on pain severity and pain interference were virtually identical to the unadjusted effects. In summary, this study of opioid-dependent patients with depressive symptoms found that treatment with escitalopram was associated with clinically meaningful reductions in pain severity and pain interference during the first three months of therapy. PMID:21924552

Short-term escitalopram treatment normalizes aberrant self-referential processing in major depressive disorder.

PubMed

Komulainen, Emma; Heikkilä, Roope; Nummenmaa, Lauri; Raij, Tuukka T; Harmer, Catherine J; Isometsä, Erkki; Ekelund, Jesper

2018-04-22

Increased self-focus and negative self-concept play an important role in depression. Antidepressants influence self-referential processing in healthy volunteers, but their function in self-processing of depressed patients remains unknown. Thirty-two depressed patients were randomly allocated to receive either escitalopram 10 mg or placebo for one week. After one week, neural responses to positive and negative self-referential adjectives and neutral control stimuli were assessed with functional magnetic resonance imaging. A group of matched healthy volunteers served as a control group. Escitalopram decreased responses of medial fronto-parietal regions to self-referential words relative to non-emotional control stimuli, driven by increased responses to the control condition. Escitalopram also increased responses in the pre-defined region of the medial prefrontal cortex (MPFC) and the anterior cingulate cortex (ACC) to positive relative to negative words. Importantly, the changes in neural responses occurred before any effect on depressive symptoms, implying a direct effect of escitalopram. Furthermore, the placebo group had decreased responses of the MPFC and the ACC to positive self-referential processing relative to the matched healthy controls. However, neural responses of the escitalopram group and the healthy unmedicated controls were similar. Differences between the groups in self-reported depression symptoms and personality traits may have influenced the results. One-week treatment with escitalopram normalized aberrant self-referential processing in depressed patients, shifting the focus from the self to the external environment and potentiating positive self-referential processing. This may be an important factor in mechanism of action of antidepressants. Copyright © 2018 Elsevier B.V. All rights reserved.

Higher serotonin transporter occupancy after multiple dose administration of escitalopram compared to citalopram: an [123I]ADAM SPECT study.

PubMed

Klein, Nikolas; Sacher, Julia; Geiss-Granadia, Thomas; Mossaheb, Nilufar; Attarbaschi, Trawat; Lanzenberger, Rupert; Spindelegger, Christoph; Holik, Alexander; Asenbaum, Susanne; Dudczak, Robert; Tauscher, Johannes; Kasper, Siegfried

2007-04-01

Previous studies have investigated the occupancy of the serotonin reuptake transporter (SERT) after clinical doses of citalopram and other selective serotonin reuptake inhibitors. In the present study, the occupancies of SERT after multiple doses of escitalopram and citalopram were compared using the radioligand [(123)I]ADAM and single photon emission computed tomography (SPECT). Fifteen healthy subjects received escitalopram 10 mg/day (n = 6) or citalopram 20 mg/day (n = 9) for a total of 10 days. SERT occupancies in midbrain were determined with SPECT and [(123)I]ADAM at three different time points: at baseline (no medication) and at 6 and 54 h after last drug intake. At 6 h after the last dose, mean SERT occupancies were 81.5 +/- 5.4% (mean+/-SD) for escitalopram and 64.0 +/- 12.7% for citalopram (p < 0.01). At 54 h after the last dose, mean SERT occupancies were 63.3 +/- 12.1% for escitalopram and 49.0 +/- 11.7% for citalopram (p < 0.05). The plasma concentrations of the S-enantiomer were of the same magnitude in both substances. For both drugs, the elimination rate of the S-enantiomer in plasma was markedly higher than the occupancy decline rate in the midbrain. The significantly higher occupancy of SERT after multiple doses of escitalopram compared to citalopram indicates an increased inhibition of SERT by escitalopram. The results can also be explained by an attenuating effect of R-citalopram on the occupancy of S-citalopram at the SERT.

Efficacy of escitalopram compared to citalopram: a meta-analysis.

PubMed

Montgomery, Stuart; Hansen, Thomas; Kasper, Siegfried

2011-03-01

The aim of this review was to assess the clinical relevance of the relative antidepressant efficacy of escitalopram and citalopram by meta-analysis. Studies in major depressive disorder (MDD) with both escitalopram and citalopram treatment arms were identified. Adult patients had to meet DSM-IV criteria for MDD. The primary outcome measure was the treatment difference in Montgomery-Asberg Depression Rating Scale (MADRS) total score at week 8 (or last assessment if <8 wk). Secondary outcome measures were response (≥ 50% improvement from baseline) and remission (MADRS ≤ 12). A search of the literature and websites found eight randomized controlled trials (RCTs) and onr naturalistic trial, with a total of 2009 patients (escitalopram, n=995; citalopram, n=1014). Escitalopram was significantly more effective than citalopram in overall treatment effect, with an estimated mean treatment difference of 1.7 points at week 8 (or last assessment if <8 wk) on the MADRS (95% CI 0.8-2.6, p=0.0002) (six RCTs used the MADRS), and in responder rate (8.3 percentage points, 95% CI 4.4-12.3) (eight RCTs) and remitter rate (17.6 percentage points, 95% CI 12.1-23.1) analyses (reported for four RCTs), corresponding to number-needed-to-treat (NNT) values of 11.9 (p<0.0001) for response and 5.7 (p<0.0001) for remission. The overall odds ratios were 1.44 (p<0.0003) for response and 1.86 (p<0.0001) for remission, in favour of escitalopram. In this meta-analysis, the statistically significant superior efficacy of escitalopram compared to citalopram was shown to be clinically relevant.

Chronic treatment with escitalopram but not R-citalopram translocates Galpha(s) from lipid raft domains and potentiates adenylyl cyclase: a 5-hydroxytryptamine transporter-independent action of this antidepressant compound.

PubMed

Zhang, Lanqiu; Rasenick, Mark M

2010-03-01

Chronic antidepressant treatment has been shown to increase adenylyl cyclase activity, in part, due to translocation of Galpha(s) from lipid rafts to a nonraft fraction of the plasma membrane where they engage in a more facile stimulation of adenylyl cyclase. This effect holds for multiple classes of antidepressants, and for serotonin uptake inhibitors, it occurs in the absence of the serotonin transporter. In the present study, we examined the change in the amount of Galpha(s) in lipid raft and whole cell lysate after exposing C6 cells to escitalopram. The results showed that chronic (but not acute) escitalopram decreased the content of Galpha(s) in lipid rafts, whereas there was no change in overall Galpha(s) content. These effects were drug dose- and exposure time-dependent. Although R-citalopram has been reported to antagonize some effects of escitalopram, this compound was without effect on Galpha(s) localization in lipid rafts, and R-citalopram did not inhibit these actions of escitalopram. Escitalopram treatment increased cAMP accumulation, and this seemed due to increased coupling between Galpha(s) and adenylyl cyclase. Thus, escitalopram is potent, rapid and efficacious in translocating Galpha(s) from lipid rafts, and this effect seems to occur independently of 5-hydroxytryptamine transporters. Our results suggest that, although antidepressants display distinct affinities for well identified targets (e.g., monoamine transporters), several presynaptic and postsynaptic molecules are probably modified during chronic antidepressant treatment, and these additional targets may be required for clinical efficacy of these drugs.

Effect of Proton Pump Inhibitors on the Serum Concentrations of the Selective Serotonin Reuptake Inhibitors Citalopram, Escitalopram, and Sertraline

PubMed Central

Gjestad, Caroline; Westin, Andreas A.; Skogvoll, Eirik

2015-01-01

Background: The selective serotonin reuptake inhibitors (SSRIs) citalopram, escitalopram, and sertraline are all metabolized by the cytochrome P-450 isoenzyme CYP2C19, which is inhibited by the proton pump inhibitors (PPIs) omeprazole, esomeprazole, lansoprazole, and pantoprazole. The aim of the present study was to evaluate the effect of these PPIs on the serum concentrations of citalopram, escitalopram, and sertraline. Methods: Serum concentrations from patients treated with citalopram, escitalopram, or sertraline were obtained from a routine therapeutic drug monitoring database, and samples from subjects concomitantly using PPIs were identified. Dose-adjusted SSRI serum concentrations were calculated to compare data from those treated and those not treated with PPIs. Results: Citalopram concentrations were significantly higher in patients treated with omeprazole (+35.3%; P < 0.001), esomeprazole (+32.8%; P < 0.001), and lansoprazole (+14.7%; P = 0.043). Escitalopram concentrations were significantly higher in patients treated with omeprazole (+93.9%; P < 0.001), esomeprazole (+81.8%; P < 0.001), lansoprazole (+20.1%; P = 0.008), and pantoprazole (+21.6%; P = 0.002). Sertraline concentrations were significantly higher in patients treated with esomeprazole (+38.5%; P = 0.0014). Conclusions: The effect of comedication with PPIs on the serum concentration of SSRIs is more pronounced for omeprazole and esomeprazole than for lansoprazole and pantoprazole, and escitalopram is affected to a greater extent than are citalopram and sertraline. When omeprazole or esomeprazole are used in combination with escitalopram, a 50% dose reduction of the latter should be considered. PMID:24887634

Chronic Treatment with Escitalopram but Not R-Citalopram Translocates Gαs from Lipid Raft Domains and Potentiates Adenylyl Cyclase: A 5-Hydroxytryptamine Transporter-Independent Action of This Antidepressant Compound

PubMed Central

Zhang, Lanqiu

2010-01-01

Chronic antidepressant treatment has been shown to increase adenylyl cyclase activity, in part, due to translocation of Gαs from lipid rafts to a nonraft fraction of the plasma membrane where they engage in a more facile stimulation of adenylyl cyclase. This effect holds for multiple classes of antidepressants, and for serotonin uptake inhibitors, it occurs in the absence of the serotonin transporter. In the present study, we examined the change in the amount of Gαs in lipid raft and whole cell lysate after exposing C6 cells to escitalopram. The results showed that chronic (but not acute) escitalopram decreased the content of Gαs in lipid rafts, whereas there was no change in overall Gαs content. These effects were drug dose- and exposure time-dependent. Although R-citalopram has been reported to antagonize some effects of escitalopram, this compound was without effect on Gαs localization in lipid rafts, and R-citalopram did not inhibit these actions of escitalopram. Escitalopram treatment increased cAMP accumulation, and this seemed due to increased coupling between Gαs and adenylyl cyclase. Thus, escitalopram is potent, rapid and efficacious in translocating Gαs from lipid rafts, and this effect seems to occur independently of 5-hydroxytryptamine transporters. Our results suggest that, although antidepressants display distinct affinities for well identified targets (e.g., monoamine transporters), several presynaptic and postsynaptic molecules are probably modified during chronic antidepressant treatment, and these additional targets may be required for clinical efficacy of these drugs. PMID:19996298

Impact of evergreening on patients and health insurance: a meta analysis and reimbursement cost analysis of citalopram/escitalopram antidepressants

PubMed Central

2012-01-01

Background "Evergreening" refers to the numerous strategies whereby owners of pharmaceutical products use patent laws and minor drug modifications to extend their monopoly privileges on the drug. We aimed to evaluate the impact of evergreening through the case study of the antidepressant citalopram and its chiral switch form escitalopram by evaluating treatment efficacy and acceptability for patients, as well as health insurance costs for society. Methods To assess efficacy and acceptability, we performed meta-analyses for efficacy and acceptability. We compared direct evidence (meta-analysis of results of head-to-head trials) and indirect evidence (adjusted indirect comparison of results of placebo-controlled trials). To assess health insurance costs, we analyzed individual reimbursement data from a representative sample of the French National Health Insurance Inter-regime Information System (SNIIR-AM) from 2003 to 2010, which allowed for projecting these results to the whole SNIIR-AM population (53 million people). Results In the meta-analysis of seven head-to-head trials (2,174 patients), efficacy was significantly better for escitalopram than citalopram (combined odds ratio (OR) 1.60 (95% confidence interval 1.05 to 2.46)). However, for the adjusted indirect comparison of 10 citalopram and 12 escitalopram placebo-controlled trials, 2,984 and 3,777 patients respectively, efficacy was similar for the two drug forms (combined indirect OR 1.03 (0.82 to 1.30)). Because of the discrepancy, we could not combine direct and indirect data (test of inconsistency, P = 0.07). A similar discrepancy was found for treatment acceptability. The overall reimbursement cost burden for the citalopram, escitalopram and its generic forms was 120.6 million Euros in 2010, with 96.8 million Euros for escitalopram. Conclusions The clinical benefit of escitalopram versus citalopram remains uncertain. In our case of evergreening, escitalopram represented a substantially high proportion of the overall reimbursement cost burden as compared with citalopram and the generic forms. PMID:23167972

Impact of evergreening on patients and health insurance: a meta analysis and reimbursement cost analysis of citalopram/escitalopram antidepressants.

PubMed

Alkhafaji, Ali A; Trinquart, Ludovic; Baron, Gabriel; Desvarieux, Moïse; Ravaud, Philippe

2012-11-20

"Evergreening" refers to the numerous strategies whereby owners of pharmaceutical products use patent laws and minor drug modifications to extend their monopoly privileges on the drug. We aimed to evaluate the impact of evergreening through the case study of the antidepressant citalopram and its chiral switch form escitalopram by evaluating treatment efficacy and acceptability for patients, as well as health insurance costs for society. To assess efficacy and acceptability, we performed meta-analyses for efficacy and acceptability. We compared direct evidence (meta-analysis of results of head-to-head trials) and indirect evidence (adjusted indirect comparison of results of placebo-controlled trials). To assess health insurance costs, we analyzed individual reimbursement data from a representative sample of the French National Health Insurance Inter-regime Information System (SNIIR-AM) from 2003 to 2010, which allowed for projecting these results to the whole SNIIR-AM population (53 million people). In the meta-analysis of seven head-to-head trials (2,174 patients), efficacy was significantly better for escitalopram than citalopram (combined odds ratio (OR) 1.60 (95% confidence interval 1.05 to 2.46)). However, for the adjusted indirect comparison of 10 citalopram and 12 escitalopram placebo-controlled trials, 2,984 and 3,777 patients respectively, efficacy was similar for the two drug forms (combined indirect OR 1.03 (0.82 to 1.30)). Because of the discrepancy, we could not combine direct and indirect data (test of inconsistency, P = 0.07). A similar discrepancy was found for treatment acceptability. The overall reimbursement cost burden for the citalopram, escitalopram and its generic forms was 120.6 million Euros in 2010, with 96.8 million Euros for escitalopram. The clinical benefit of escitalopram versus citalopram remains uncertain. In our case of evergreening, escitalopram represented a substantially high proportion of the overall reimbursement cost burden as compared with citalopram and the generic forms.

Serotonin Signal Transduction in Two Groups of Autistic Patients

DTIC Science & Technology

2013-12-01

modification as learned from the initial studies. Treat cells with escitalopram or r-citalopram and test for increased coupling between G proteins and...improved medications. 6 Figure 1 (above). Escitalopram translocates Gs in cells obtained from High 5HT subjects. Lymphoblasts from High...5HT/High IS or Normal 5HT/moderate IS (two lines each) were grown in suspension and treated with escitalopram or control (r-citalopram, @10 µM) for

Need for common internal controls when assessing the relative efficacy of pharmacologic agents using a meta-analytic approach: case study of cyclooxygenase 2-selective inhibitors for the treatment of osteoarthritis.

PubMed

Lee, Chin; Hunsche, Elke; Balshaw, Robert; Kong, Sheldon X; Schnitzer, Thomas J

2005-08-15

To evaluate the role of common internal controls in a meta-analysis of the relative efficacy of cyclooxygenase 2-selective inhibitors (coxibs) in the treatment of osteoarthritis (OA). A systematic search of Medline and US Food and Drug Administration electronic databases was performed to identify randomized, placebo-controlled clinical trials of coxibs (etoricoxib, celecoxib, rofecoxib, valdecoxib) in patients with hip and/or knee OA. The effect size for coxibs and common active internal controls (nonsteroidal antiinflammatory drugs [NSAIDs], naproxen) were determined by the mean changes from baseline in Western Ontario and McMaster Universities Osteoarthritis Index pain subscores as compared with placebo. The effect size for all coxib groups combined (0.44) indicated greater efficacy as compared with placebo, but significant heterogeneity (P < 0.0001) was observed. Rofecoxib at dosages of 12.5 mg/day and 25 mg/day and etoricoxib at a dosage of 60 mg/day had similar effect sizes (0.68 and 0.73, respectively), but these effect sizes were comparatively greater than those for both celecoxib at dosages of 200 mg/day and 100 mg twice daily or valdecoxib at a dosage of 10 mg/day (0.26 and 0.16, respectively). The effect sizes for NSAIDs or naproxen versus placebo, as determined using data from rofecoxib/etoricoxib trials, were consistently higher than the effect sizes derived from trials of celecoxib/valdecoxib. Significant heterogeneity was present in the overall effect size for NSAIDs (P = 0.007) and naproxen (P = 0.04) groups based on data available from all coxib trials. Coxibs and common active internal controls showed larger effect sizes versus placebo in the rofecoxib/etoricoxib trials than in the celecoxib/valdecoxib trials. These findings suggest systematic differences among published coxib trials and emphasize the need for direct-comparison trials. In the absence of such trials, common internal controls should be assessed when performing indirect meta-analytic comparisons.

Effect of Escitalopram on Mental Stress-Induced Myocardial Ischemia: The Results of the REMIT Trial

PubMed Central

Jiang, Wei; Velazquez, Eric J.; Kuchibhatla, Maragatha; Samad, Zainab; Boyle, Stephen H.; Kuhn, Cynthia; Becker, Richard C.; Ortel, Thomas L.; Williams, Redford B.; Rogers, Joseph G.; O’Connor, Christopher

2015-01-01

Importance Mental-stress-induced myocardial ischemia (MSIMI) is an intermediate surrogate endpoint representing the pathophysiological link between psychosocial risk factors and adverse outcomes of coronary heart disease (CHD). However, pharmacological interventions aimed at reducing MSIMI have not been well studied. Objective To examine the effects of 6 weeks of escitalopram treatment vs. placebo on MSIMI and other psychological stress-related biophysiological and emotional parameters. Design, Setting, and Participants The REMIT study is a randomized, double-blind, placebo-controlled trial of patients with clinically stable CHD and laboratory MSIMI. Enrollment occurred from 7/24/2007–8/24/2011 at a tertiary medical center. Interventions Eligible participants were randomized 1:1 to receive escitalopram (dose began at 5 mg with titration to 20 mg/day in 3 weeks) or placebo over 6 weeks. Main Outcome Measure Occurrence of MSIMI, defined as (1) development or worsening of regional wall motion abnormality; (2) left ventricular ejection fraction reduction ≥8%; and/or (3) horizontal or downsloping ST-segment depression ≥1mm in ≥2 leads lasting for ≥3 consecutive beats during ≥1 of 3 mental tasks. Results 127 participants were randomized to escitalopram (n=64) or placebo (n=63); 112 (96.1%) completed endpoint assessments (n=56 in each arm). At the end of 6 weeks, more patients taking escitalopram (34.2% [95% CI, 25.4 to 43.0]) had absence of MSIMI during the 3 mental stressors compared with patients taking placebo (17.5% [95% CI, 10.4 to 24.5]) based on unadjusted multiple imputation model for intention-to-treat analysis. A significant difference favoring escitalopram was observed (OR=2.62 [95% CI, 1.06 to 6.44]). Rates of exercise-induced ischemia were slightly lower at 6 weeks in the escitalopram group (45.8% [95% CI, 36.6 to 55.0]) than in patients receiving placebo (52.5% [95% CI, 43.3 to 61.7]), compared with baseline escitalopram (49.2% [95% CI, 39.9 to 58.5]) vs placebo (56.7% [95% CI, 47.5 to 65.9]), but this difference was not statistically significant. Conclusion and relevance Among patients with stable CHD and baseline MSIMI, 6 weeks of escitalopram versus placebo resulted in lower prevalence of MSIMI. There was no difference in exercise-induced ischemia. Trial Registration ClinicalTrials.gov Identifier: NCT00574847 PMID:23695483

Augmentation by escitalopram, but not citalopram or R-citalopram, of the effects of low-dose risperidone: behavioral, biochemical, and electrophysiological evidence.

PubMed

Marcus, Monica M; Jardemark, Kent; Malmerfelt, Anna; Gertow, Jens; Konradsson-Geuken, Asa; Svensson, Torgny H

2012-04-01

Antidepressant drugs are frequently used to treat affective symptoms in schizophrenia. We have recently shown that escitalopram, but not citalopram or R-citalopram, increases firing rate and burst firing of midbrain dopamine neurons, potentiates cortical N-methyl-D-aspartate (NMDA) receptor-mediated transmission and enhances cognition, effects that might influence the outcome of concomitant antipsychotic medication. Here, we studied, in rats, the behavioral and neurobiological effects of adding escitalopram, citalopram, or R-citalopram to the second-generation antipsychotic drug risperidone. We examined antipsychotic efficacy using the conditioned avoidance response (CAR) test, extrapyramidal side effect (EPS) liability using a catalepsy test, dopamine outflow in the medial prefrontal cortex (mPFC) and nucleus accumbens using in vivo microdialysis in freely moving animals, and NMDA receptor-mediated transmission in the mPFC using intracellular electrophysiological recording in vitro. Only escitalopram (5 mg/kg), but not citalopram (10 mg/kg), or R-citalopram (10 mg/kg), dramatically enhanced the antipsychotic-like effect of a low dose of risperidone (0.25 mg/kg), without increasing catalepsy. Given alone, escitalopram, but not citalopram or R-citalopram, markedly enhanced both cortical dopamine output and NMDA receptor-mediated transmission. Addition of escitalopram and to some extent R-citalopram, but not citalopram, significantly enhanced both cortical dopamine output and cortical NMDA receptor-mediated transmission induced by a suboptimal dose/concentration of risperidone. These results suggest that adjunct treatment with escitalopram, but not citalopram, may enhance the effect of a subtherapeutic dose of risperidone on positive, negative, cognitive, and depressive symptoms in schizophrenia, yet without increased EPS liability. Copyright © 2011 Wiley Periodicals, Inc.

Population pharmacokinetics and pharmacodynamics of escitalopram in overdose and the effect of activated charcoal

PubMed Central

van Gorp, Freek; Duffull, Stephen; Hackett, L Peter; Isbister, Geoffrey K

2012-01-01

AIMS To describe the pharmacokinetics and pharmacodynamics (PKPD) of escitalopram in overdose and its effect on QT prolongation, including the effectiveness of single dose activated charcoal (SDAC). METHODS The data set included 78 escitalopram overdose events (median dose, 140 mg [10–560 mg]). SDAC was administered 1.0 to 2.6 h after 12 overdoses (15%). A fully Bayesian analysis was undertaken in WinBUGS 1.4.3, first for a population pharmacokinetic (PK) analysis followed by a PKPD analysis. The developed PKPD model was used to predict the probability of having an abnormal QT as a surrogate for torsade de pointes. RESULTS A one compartment model with first order input and first-order elimination described the PK data, including uncertainty in dose and a baseline concentration for patients taking escitalopram therapeutically. SDAC reduced the fraction absorbed by 31% and reduced the individual predicted area under the curve adjusted for dose (AUCi/dose). The absolute QT interval was related to the observed heart rate with an estimated individual heart rate correction factor (α = 0.35). The heart rate corrected QT interval (QTc) was linearly dependent on predicted escitalopram concentration [slope = 87 ms/(mg l–1)], using a hypothetical effect-compartment (half-life of effect-delay, 1.0h). Administration of SDAC significantly reduced QT prolongation and was shown to reduce the risk of having an abnormal QT by approximately 35% for escitalopram doses above 200 mg. CONCLUSIONS There was a dose-related lengthening of the QT interval that lagged the increase in drug concentration. SDAC resulted in a moderate reduction in fraction of escitalopram absorbed and reduced the risk of the QT interval being abnormal. PMID:21883384

Treatment persistence & health care costs of adult MDD patients treated with escitalopram vs. citalopram in a medicaid population.

PubMed

Wu, Eric Q; Ben-Hamadi, Rym; Lu, Mei; Beaulieu, Nicolas; Yu, Andrew P; Erder, M Haim

2012-01-01

Compare treatment persistence and health care costs of major depressive disorder (MDD) Medicaid patients treated with escitalopram versus citalopram. Retrospective analysis of Medicaid administrative claims data. Analyzed administrative claims data from the Florida Medicaid program (07/2002-06/2006) for patients ages 18-64 years with 21 inpatient claim or 2 independent medical claims for MDD. Outcomes included discontinuation and switching rates and prescription drug, medical, and total health care costs, all-cause and related to mental disorder. Contingency table analysis and survival analysis were used to compare outcomes between treatment groups, using both unadjusted analysis and multivariate analysis adjusting for baseline characteristics. The study included 2,650 patients initiated on escitalopram and 630 patients initiated on citalopram. Patients treated with escitalopram were less likely to discontinue the index drug (63.7% vs. 68.9%, P=0.015) or to switch to another second-generation antidepressant (14.9% vs. 18.4%, P=0.029) over the six months post-index date. Patients treated with escitalopram had $1,014 lower total health care costs (P=0.032) and $519 lower health care costs related to mental disorder (P=0.023). More than half of the total cost difference was attributable to savings in inpatient hospitalizations related to mental disorder ($571, P=0.003) and to outpatient costs ($53, P<0.001). Escitalopram therapy was also associated with $736 lower medical costs related to mental disorder (P=0.009). In the Florida Medicaid program, compared to adult MDD patients initiated on citalopram, escitalopram patients have better treatment persistence and lower total health care costs due to any cause and due to mental disorder, mostly driven by lower hospitalization costs related to mental disorder.

Multicenter, randomized, placebo-controlled, double-blind clinical trial of escitalopram on the progression-delaying effects in Alzheimer's disease.

PubMed

Choe, Young Min; Kim, Ki Woong; Jhoo, Jin Hyeong; Ryu, Seung Ho; Seo, Eun Hyun; Sohn, Bo Kyung; Byun, Min Soo; Bak, Jae-Hwa; Lee, Jong-Min; Yun, Hyuk Jin; Han, Myeong-Il; Woo, Jong Inn; Lee, Dong Young

2016-07-01

A series of preclinical studies have suggested that selective serotonin reuptake inhibitor antidepressants not only stimulate neurogenesis but also have neuroprotective effects. The present study primarily aimed to investigate whether escitalopram would decelerate the brain atrophy of patients with mild-to-moderate Alzheimer's disease (AD). We also assessed the effects of escitalopram on the cognitive function and neuropsychiatric symptoms of these participants. Seventy-four probable AD patients without major depression were recruited from four dementia clinics of university hospitals and randomly assigned in a 1:1 ratio. Each group received 20 mg/day of escitalopram or placebo for 52 weeks. The primary outcome measures were the change rates of hippocampal and whole brain volume on magnetic resonance imaging for 52 weeks. The Alzheimer's Disease Assessment Scale-cognitive subscale, Mini-Mental State Examination, Neuropsychiatric Inventory, and Cornell Scale for Depression in Dementia (CSDD) were also applied. We did not find any significant differences in the changes of hippocampal or whole brain volume between the groups. Escitalopram showed significant beneficial effects on the CSDD score at 28 weeks compared with placebo (t = -2.17, df = 50.42, p = 0.035), but this finding did not persist throughout the study. The findings of the present study do not support the role of escitalopram as a progression-delaying treatment for AD. However, the negative results of the present trial should be interpreted cautiously because of the relatively small sample size. Further large-scale escitalopram trials targeting the earlier stages of AD, even prodromal AD, are still needed. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

A shift toward T helper 2 responses and an increase in modulators of innate immunity in depressed patients treated with escitalopram.

PubMed

Ho, Pei-Shen; Yeh, Yi-Wei; Huang, San-Yuan; Liang, Chih-Sung

2015-03-01

Depression is hypothesized to involve inflammatory processes, and identifying the key cytokines targeted by antidepressant drugs is critical for tailoring treatment to specific cases. However, investigating a limited number of cytokines at one time cannot provide a broad picture of antidepressant-associated immunomodulation. Cytokines act in a network where one could demonstrate pleiotropism, redundancy, synergy, and antagonism with other cytokine functions. This study was aimed at determining whether escitalopram functions as an anti-inflammatory agent and, if so, how it influences cytokine networks. A total of 24 healthy controls and 26 patients with clinical depression requiring inpatient treatment were recruited. A multiplex assay, an efficient tool to simultaneously measure 27 cytokines, was applied in patients with depression before and after 4-week escitalopram treatment. Healthy controls did not take escitalopram and completed cytokine analyses once. We demonstrated that escitalopram increased the levels of interleukin (IL)-1 receptor antagonist and IL-2. Moreover, escitalopram contributed to a shift toward T helper 2 responses and an increase in modulators of innate immunity, leading to a decrease of immune system activation, both innate and adaptive. We suggest that escitalopram modulates the balance of IL-1 and IL-1 receptor antagonist and improves the function and number of T regulatory cells. However, diverse conclusions could be drawn if only a few cytokines were assessed or different significance levels were used. Further studies should investigate a wide range of cytokines in a reliable and valid way, which is key to disentangling the effects of different antidepressants on inflammatory processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Early effect on general interest, and short-term antidepressant efficacy and safety of agomelatine (25-50mg/day) and escitalopram (10-20mg/day) in outpatients with Major Depressive Disorder. A 12-week randomised double-blind comparative study.

PubMed

Udristoiu, T; Dehelean, P; Nuss, Ph; Raba, V; Picarel-Blanchot, F; de Bodinat, C

2016-07-15

A double-blind, randomized, study was conducted in 29 centers in Romania to evaluate the effect of agomelatine 25-50mg/day (n=144 patients) on general interest, overall clinical efficacy, and functionality in comparison with escitalopram 10-20mg/day (n=143 patients) in out-patients diagnosed with moderate to severe Major Depressive Disorder (MDD). The primary endpoint of the study was the score difference between agomelatine and escitalopram were assessed on the item 13 of the Quick Inventory of Depressive Symptomatology (16-Item) Self-Report (QIDS-SR16) over the first week period. Secondary measures include the primary criterion on the 12-week period, the within-group evolution over 12 weeks of the 17-item Hamilton Depression Scale (HAM-D17) total score, CGI severity of illness (CGI-S) and CGI-I scores, and functionality by using the self-rated Sheehan Disability Scale (SDS). After one week, the mean General Interest score showed no statistically significant difference between treatments. Over 12 weeks, patients felt more and more interested in other people and activities than before having taken medication. Both agomelatine and escitalopram improved depressive symptoms and symptom-related functional impairment of patients. Both agomelatine and escitalopram were well-tolerated by patients. The strength of our results would benefit from additional data from trials using a similar design and other active comparators. There was no difference in week 1 changes of interest between agomelatine and escitalopram. The relatively good tolerability of agomelatine and escitalopram is confirmed. Copyright © 2016 Elsevier B.V. All rights reserved.

Low proarrhythmic potential of citalopram and escitalopram in contrast to haloperidol in an experimental whole-heart model.

PubMed

Frommeyer, Gerrit; Brücher, Benedict; von der Ahe, Henning; Kaese, Sven; Dechering, Dirk G; Kochhäuser, Simon; Bogossian, Harilaos; Milberg, Peter; Eckardt, Lars

2016-10-05

In several case reports proarrhythmic effects of citalopram and escitalopram have been reported. Systematic analyses on prorarrhythmic effects of these drugs are not yet available. The aim of the present study was to investigate if application of citalopram, escitalopram or haloperidol provokes polymorphic ventricular tachycardia in a sensitive model of proarrhythmia. In isolated rabbit hearts monophasic action potentials and ECG showed a significant QT-prolongation after application of citalopram (2µM: +47ms, 4µM: +56ms, P<0.05) accompanied by an increase of action potential duration (APD) but not dispersion of repolarization. Reduced potassium concentration in bradycardic AV-blocked hearts provoked early afterdepolarizations (EAD) in 2 of 12 hearts but no polymorphic ventricular tachycardia (pVT). Application of escitalopram also increased QT-interval (2µM: +3ms, 4µM: +30ms, P<0.05) and APD without effects on dispersion. 3 of 10 hearts showed EAD and pVT in 2 of 10 hearts (32 episodes). The results were compared to 12 rabbits treated with haloperidol which led to an increase in QT-interval (1µM:+62ms; 2µM:+96ms; P<0.01), APD and dispersion (1µM:+15ms, 2µM:+40ms; P<0.01) and induced EAD in all 12 and pVT in 10 of 12 hearts (152 episodes). Citalopram and escitalopram demonstrated a rather safe electrophysiologic profile despite significant QT prolongation. In contrast, haloperidol led to significant increase of dispersion of repolarization while this parameter remained stable under the influence of citalopram or escitalopram. These results imply that application of citalopram or escitalopram is not as proarrhythmic as some case reports might suggest while haloperidol is torsadogenic. Copyright © 2016 Elsevier B.V. All rights reserved.

17β-Estradiol augments antidepressant efficacy of escitalopram in ovariectomized rats: Neuroprotective and serotonin reuptake transporter modulatory effects.

PubMed

Ibrahim, Weam W; Safar, Marwa M; Khattab, Mahmoud M; Agha, Azza M

2016-12-01

The prevalence or recurrence of depression is seriously increased in women during the transition to and after menopause. The chronic hypo-estrogenic state of menopause may reduce the response to antidepressants; however the influence of estrogen therapy on their efficacy is still controversial. This study aimed at investigating the effects of combining escitalopram with 17β-estradiol on depression and cognitive impairment induced by ovariectomy, an experimental model of human menopause. Young adult female Wistar rats were subjected to either sham operation or ovariectomy. Ovariectomized animals were treated chronically with escitalopram (10mg/kg/day, i.p) alone or with four doses of 17β-estradiol (40μg/kg, s.c) given prior to the behavioral tests. Co-administration of 17β-estradiol improved escitalopram-induced antidepressant effect in forced swimming test verified as more prominent decrease in the immobility time without opposing its memory enhancing effect in Morris water maze. 17β-estradiol augmented the modulatory effects of escitalopram on the hippocampal levels of brain-derived neurotrophic factor and serotonin reuptake transporter as well as tumor necrosis factor-alpha without altering its effects on the gene expressions of serotonin receptor 1A, estrogen receptors alpha and beta, or acetylcholinestearase content. This combined therapy afforded synergistic protective effects on the brain histopathological architecture, particularly, the hippocampus. The antidepressant effect of 17β-estradiol was abolished by pretreatment with estrogen receptor antagonist, tamoxifen (10mg/kg, p.o). In conclusion, 17β-estradiol-induced antidepressant effect was confined to intracellular estrogen receptors activation. Moreover, 17β-estradiol enhanced escitalopram's efficiency in ameliorating menopausal-like depression, via exerting synergistic neuroprotective and serotonin reuptake transporter modulatory effects, without impeding escitalopram-mediated cognitive improvement. Copyright © 2016 Elsevier Ltd. All rights reserved.

A comparative study of QT prolongation with serotonin reuptake inhibitors.

PubMed

Ojero-Senard, Ana; Benevent, Justine; Bondon-Guitton, Emmanuelle; Durrieu, Geneviève; Chebane, Leila; Araujo, Melanie; Montastruc, Francois; Montastruc, Jean-Louis

2017-10-01

QT interval prolongations were described with citalopram and escitalopram. However, the effects of the other serotonin reuptake inhibitors (SRIs) remained discussed. In order to identify a putative signal with other SRIs, the present study investigates the reports of QT interval prolongation with SRIs in two pharmacovigilance databases (PVDB). Two kinds of investigations were performed: (1) a comparative study in VigiBase®, the WHO PVDB, where notifications of QT prolongation with six SRIs (citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, sertraline) were selected. Cases with overdose or pregnancy were excluded. The relationship between the "suspected" SRI and occurrence of QT prolongation was assessed by calculating reporting odds ratio (ROR) in a case/non-case design. (2) A descriptive study of QT prolongation reports with citalopram and escitalopram in the French FPVD. In VigiBase®, 855 notifications were identified (mean age 56.2 years, mainly women 73%). Among them, 172 (20.1%) were associated to escitalopram; 299 (35.0%), to citalopram; 186 (21.8%), to fluoxetine; 94 (11.0%), to sertraline; 66 (7.7%), to paroxetine; and 38 (4.4%) to fluvoxamine. A significant ROR value (higher than 1) was only found for citalopram (3.35 CI95% [2.90-3.87]) or escitalopram (2.50 [2.11-2.95]). In the FPVD, eight reports of QT prolongation were found with citalopram and 27 with escitalopram, mainly in women (77.1%) with a mean age of 73.2 years. In 23 cases (66%), SRIs were associated with other suspected drugs, mainly cardiotropic or psychotropic ones. Hypokalemia was associated in six patients. This study, performed in real conditions of life, shows a clear signal of QT prolongation with only two SRIs, citalopram and escitalopram, indicating that QT prolongation is not a SRI class effect.

Serotonin Signal Transduction in Two Groups of Autistic Patients

DTIC Science & Technology

2012-10-01

as learned from the initial studies. Treat cells with escitalopram or r-citalopram and test for increased coupling between G proteins and effector...Figure 1 (top). Escitalopram translocates Gs in cells obtained from High 5HT subjects. Lymphoblasts from High 5HT/High IS or Normal 5HT/moderate IS...two lines each) were grown in suspension and treated with escitalopram or control (r-citalopram, @10 µM) for 3days, harvested and membranes were

A Randomized Placebo-Controlled Trial of Citalopram for Anxiety Disorders Following Traumatic Brain Injury

DTIC Science & Technology

2005-04-01

WRAMC and all other sites in the multi-center study have been trained to use our electronic data capture system. Recent literature on Escitalopram , the...Disorder (GAD). Based on the merits of three placebo- controlled studies, Forest Laboratories announced the FDA approval of Escitalopram for the treatment...therefore there are no conclusions that can be made at this time. References: Davidson JR, Bose A, Korotzer A, Hongije Z. Escitalopram in the

The allosteric citalopram binding site differentially interferes with neuronal firing rate and SERT trafficking in serotonergic neurons.

PubMed

Matthäus, Friederike; Haddjeri, Nasser; Sánchez, Connie; Martí, Yasmina; Bahri, Senda; Rovera, Renaud; Schloss, Patrick; Lau, Thorsten

2016-11-01

Citalopram is a clinically applied selective serotonin re-uptake inhibitor for antidepressant pharmacotherapy. It consists of two enantiomers, S-citalopram (escitalopram) and R-citalopram, of which escitalopram exerts the antidepressant therapeutic effect and has been shown to be one of the most efficient antidepressants, while R-citalopram antagonizes escitalopram via an unknown molecular mechanism that may depend on binding to a low-affinity allosteric binding site of the serotonin transporter. However, the precise mechanism of antidepressant regulation of the serotonin transporter by citalopram enantiomers still remains elusive. Here we investigate escitalopram׳s acute effect on (1) serotonergic neuronal firing in transgenic mice that express the human serotonin transporter without and with a mutation that disables the allosteric binding site, and (2) regulation of the serotonin transporter׳s cell surface localization in stem cell-derived serotonergic neurons. Our results demonstrate that escitalopram inhibited neuronal firing less potently in the mouse line featuring a mutation that abolishes the function of the allosteric binding site and induced serotonin transporter internalization independently of the allosteric binding site mechanism. Furthermore, citalopram enantiomers dose-dependently induced serotonin transporter internalization. In conclusion, this study provides new insight into antidepressant effects exerted by citalopram enantiomers in presence and absence of a functional allosteric binding site. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

Status of etoricoxib in the treatment of rheumatic diseases. Expert panel opinion

PubMed Central

Majdan, Maria; Mastalerz-Migas, Agnieszka; Niewada, Maciej; Skrzydło-Radomańska, Barbara; Mamcarz, Artur

2017-01-01

Pain is one of the most disabling symptoms of rheumatoid diseases. Patients with pain secondary to osteoarthritis (OA), rheumatoid arthritis (RA), ankylosing spondylitis (AS) or gout require effective analgesic treatment, and the physician’s task is to select a drug that is best suited for an individual patient. The choice of pharmacotherapy should be based both on drug potency and clinical efficacy, and its safety profile, particularly in the elderly population, as the number of comorbidities (and hence the risk of treatment complications and drug interactions) rises with age. In cases involving a high risk of gastrointestinal complications or concerns about hepatotoxicity, with a low cardiovascular risk, the first-line nonsteroidal anti-inflammatory drugs to consider should be coxibs including etoricoxib. PMID:29491537

Efficacy and tolerability of escitalopram versus citalopram in major depressive disorder: a 6-week, multicenter, prospective, randomized, double-blind, active-controlled study in adult outpatients.

PubMed

Yevtushenko, Valery Y; Belous, Alexander I; Yevtushenko, Yevgenia G; Gusinin, Sergei E; Buzik, Oleg J; Agibalova, Tatiana V

2007-11-01

The S-enantiomer of citalopram (escitalopram) is the active moiety linked to the anti-depressant effects associated with citalopram (the racemate). For escitalopram to be approved for the treatment of depression in Europe, findings from clinical trials of escitalopram are required to match previous results from studies of the racemate, citalopram. The aim of this study was to compare the efficacy and tolerability of escitalopram and citalopram in outpatients with major depressive disorder (MDD). This prospective, randomized, double-blind, active-controlled study was conducted at 8 psychiatric outpatient clinics in the Federation of Russia. Adult outpatients aged 25 to 45 years with MDD and a total score > or =25 on the Montgomery-Asberg Depression Rating Scale (MADRS) were eligible. Patients were randomly assigned to receive 6 weeks of treatment with fixed daily doses of escitalopram 10 mg, citalopram 10 mg, or citalopram 20 mg. Efficacy assessments were made at weeks 0 (baseline), 1, 4, and 6 (study end or last observation carried forward). The primary efficacy parameter was the change from baseline in MADRS total score. Secondary measures were the change from baseline in MADRS total score in a subgroup of severely depressed patients (baseline MADRS total score, > or =35), MADRS core depression subscale score, and Clinical Global Impression-Severity and Improvement (CGI-S and CGI-I) scores; and the proportions of patients classified as responders and remitters at study end. Tolerability was assessed using adverse events (AEs) recorded by the investigator. Of 330 assessable randomized patients, 8 withdrew, including 7 who withdrew consent and 1 who withdrew due to recurrence of a preexisting event. Thus, 322 patients were included in the assessment (mean age, 35 years; 41.6% male; all white; escitalopram 10 mg, 108 patients; citalopram 10 mg, 106; citalopram 20 mg, 108). At study end, the mean (SE) change from baseline in MADRS total score was significantly greater in the escitalopram arm than in the 10- and 20-rag citalopram arms (-28.70 [0.78] vs -20.11 [0.80] and -25.19 [0.78]; both, P < 0.001). Improvements were more marked in the severely depressed subgroup (-30.33 [0.95] vs -20.87 [0.99] and -26.34 [0.91]). Changes in the CGI-S and CGI-I scores and the rates of response and remission were significantly greater in the escitalopram group compared with those in the citalopram 10- and 20-mg groups (CGI-S: -2.60 [0.10] vs -1.61 [0.10] and -2.05 [0.10]; CGI-I: +1.58 [0.09] vs +2.35 [0.10] and +1.80 [0.09]; response: 95.4% vs 44.3% and 83.3%; remission: 89.8% vs 25.5% and 50.9% [all, P < 0.001]). Mean (SE) changes from baseline in core depression subscale score were -19.00 (0.59), -13.00 (0.60), and -16.52 (0.58) with escitalopram, citalopram 10 mg, and citalopram 20 mg, respectively. The prevalence of AEs was significantly lower in the escitalopram group (7) compared with the citalopram groups (16 and 19 in the 10- and 20-mg groups, respectively; both, P < 0.05). Nausea (2 [1.9%], 5 [4.7%], and 7 [6.5%] patients in the escitalopram and citalopram 10- and 20-mg groups, respectively) and headache (1 [0.9%], 2 [1.9%], and 4 [3.7%]) were the most frequently reported AEs. The results from this study suggest that escitalopram 10 mg was more effective than citalopram 10 and 20 mg at 6 weeks in these adult outpatients with MDD. All treatments were well tolerated. Copyright (c) 2007 Excerpta Medica, Inc.

Impact of cytochrome P450 2C19 polymorphisms on citalopram/escitalopram exposure: a systematic review and meta-analysis.

PubMed

Chang, Ming; Tybring, Gunnel; Dahl, Marja-Liisa; Lindh, Jonatan D

2014-09-01

Citalopram and escitalopram, selective serotonin reuptake inhibitors, are primarily metabolized by cytochrome P450 (CYP) 2C19, which is a highly polymorphic enzyme known to cause inter-individual differences in pharmacokinetics. However, the impact of CYP2C19 polymorphisms on citalopram or escitalopram exposure has yet to be fully clarified, especially with regard to the quantitative impact of the CYP2C19*17 allele. The objective of this study was to quantify the effect of functional CYP2C19 allele variants on citalopram/escitalopram exposure. We performed a systematic review and meta-analysis with a structured search algorithm and eligibility criteria for including related studies, calculating the change of citalopram or escitalopram exposure associated with CYP2C19*2, *3, and *17 as compared with CYP2C19*1 using fixed-effect and random-effects models. Assessment of publication bias was performed by means of funnel plots and sensitivity analysis using meta-regressions. The pre-defined review protocol was registered at the PROSPERO international prospective register of systematic reviews, registration number CRD42013004106. Sixteen studies from 14 publications met the inclusion criteria. Eligible studies included 847 patients from psychiatric patient trials and 140 healthy subjects from pharmacokinetic studies. Compared to subjects with the EM/EM (CYP2C19*1/*1) genotype, the exposure to (es)citalopram increased by 95 % (95 % CI 40-149, p < 0.0001) in the poor metabolizer (PM)/PM (CYP2C19*2 or *3/*2 or *3), 30 % (95 % CI 4-55, p < 0.05) in the extensive metabolizer (EM)/PM (CYP2C19*1/*2 or *3), and 25 % (95 % CI 1-49, p < 0.05) in the ultrarapid metabolizer (UM)/PM (CYP2C19*17/*2 or *3) groups. In contrast, the exposure to (es)citalopram decreased by 36 % (95 % CI 27-46, p < 0.0001) in the UM/UM (CYP2C19*17/*17) and by 14 % (95 % CI 1-27, p < 0.05) in the UM/EM (CYP2C19*17/*1). This is the first meta-analysis based on a systematic review of accumulated information that addresses the relationship between CYP2C19 genotypes and the exposure to citalopram or escitalopram. All functional CYP2C19 genotype groups demonstrated significant effects on (es)citalopram exposure. The findings based on our pooled analysis are likely to help in understanding the inter-individual variability in the exposure to citalopram and escitalopram in psychiatric patients and to facilitate dose selection, particularly for the homozygous carriers of CYP2C19*2 or *3 (loss of function) and CYP2C19*17 (gain of function) alleles. The results could improve individualization of citalopram or escitalopram therapy and could also be used for physiologically based pharmacokinetic modeling as well as pharmacokinetic/pharmacodynamic modeling.

A pharmacoeconomic evaluation of escitalopram versus citalopram in the treatment of severe depression in the United Kingdom.

PubMed

Wade, Alan G; Toumi, Idris; Hemels, Michiel E H

2005-04-01

Severe depression can increase the risk of psychiatric hospitalization, as well as inpatient and outpatient care; it may also lead to long-term absenteeism from work. However, the cost-effectiveness of antidepressant therapy for severe depression has been little studied. The aim of this work was to investigate the cost-effectiveness of escitalopram compared with citalopram in patients with severe depression (Montgomery-Asberg Depression Rating Scale [MADRS] total score > or = 30) in the United Kingdom. A probabilistic decision tree with a 6-month time horizon was adapted to the UK setting. The model incorporated clinical data, resource use directly related with care of severe depression, and lost productivity costs due to absenteeism. Primary results were remission (MADRS < or = 12) and costs (in year-2003 British pounds [1.00 British pound = 0.62 US dollars in January 2003]) of treatment calculated from the perspectives of UK society and the National Health Service (NHS). Secondary outcome was first-line success of treatment (ie, remission [MADRS < or = 12] without switch of drug). Remission, discontinuation, and response rates were derived from a meta-analysis of 506 patients with severe depression and extrapolated to 6 months. Standard UK price lists and literature were used to identify costs of resources. Societal costs of lost productivity were calculated using the human capital approach. Treatment of patients with escitalopram instead of citalopram rendered a higher overall remission rate (relative difference, 10.3%) and first-line success rate (relative difference, 35.4%). The mean cost per successfully treated patient was 15.7% (146 British pounds) lower for escitalopram (786 British pounds [range, 702-876 British pounds]) compared with citalopram (932 British pounds [range, 843-1028 British pounds]) from the NHS perspective and 15.6% (238 British pounds) lower for escitalopram (1283 British pounds [range, 1157-1419 British pounds]) than for citalopram (1521 British pounds [range, 1383-1675 British pounds]) from the societal perspective. The mean cost per severely depressed patient treated (overall study group) was 32 British pounds lower for escitalopram (422 British pounds [range, 404-441 British pounds]) than citalopram (454 British pounds [range, 436-471 British pounds]) from an NHS perspective and 50 British pounds lower for escitalopram (690 British pounds [range, 665-714 British pounds]) than citalopram (740 British pounds [range, 715-767 British pounds]) from the societal perspective. Using multivariate sensitivity analyses, we found that, in 99.8% of the cases, escitalopram was dominant from both perspectives at all ranges of probabilities tested. A sensitivity analysis on the acquisition cost of citalopram verified that, from the societal perspective, escitalopram remained the dominant strategy, even at a cost of 0.00 British pounds for citalopram. These results suggest that escitalopram is a cost-saving alternative to citalopram for the treatment of severe depression in the United Kingdom from the perspectives of both the NHS and society. Therefore, a possible advantage may exist at the population level in the treatment of severe depression with escitalopram in the United Kingdom.

Efficacy and safety of escitalopram versus citalopram in major depressive disorder: a 6-week, multicenter, randomized, double-blind, flexible-dose study.

PubMed

Ou, Jian-Jun; Xun, Guang-Lei; Wu, Ren-Rong; Li, Le-Hua; Fang, Mao-Sheng; Zhang, Hong-Geng; Xie, Shi-Ping; Shi, Jian-Guo; Du, Bo; Yuan, Xue-Qin; Zhao, Jing-Ping

2011-02-01

S-citalopram (escitalopram) is the very active moiety of citalopram. It has been shown in many studies to be an effective and safe antidepressant for treating major depressive disorder (MDD). The aim of our study was to compare the efficacy and safety of escitalopram vs citalopram in Chinese MDD patients. In the double-blind study, 240 MDD patients were randomly assigned to treatment for 6 weeks either with escitalopram (10-20 mg/d) or citalopram (20-40 mg/d). The primary efficacy measurement was the change of 17-item Hamilton Depression Rating Scale (HAMD-17) total score from baseline to the end of study. The secondary efficacy measurements were response and remission rates. The adverse events (AEs) were recorded by the investigator. Two hundred and three (85%) patients completed the trial. The average dose was 13.9 mg/d in the escitalopram group and 27.6 mg/d in the citalopram group. No significant differences were found between the two groups in the change in HAMD-17 total score, response, and remission rate. These results were similar in severe MDD patients. No significant differences were found between the two groups in AEs. No serious AEs were observed in this study. The study suggests that escitalopram 10-20 mg/d are as effective and safe as citalopram 20-40 mg/d in the short-term treatment for Chinese MDD patients.

Danish physicians' preferences for prescribing escitalopram over citalopram and sertraline to treatment-naïve patients: a national, register-based study.

PubMed

Poulsen, Karen Killerup; Glintborg, Dorte; Moreno, Søren Ilsøe; Thirstrup, Steffen; Aagaard, Lise; Andersen, Stig Ejdrup

2013-05-01

To investigate whether general practitioners, hospital physicians and specialized practitioners in psychiatry have similar preferences for initiating treatment with expensive serotonin-specific reuptake inhibitors (SSRIs). All first-time prescriptions for the SSRIs escitalopram, citalopram and sertraline reported to the Danish National Register of Medicinal Product Statistics from April 1, 2009 until March 31, 2010 were analysed with regard to treatment naivety and type of prescriber. A prescription was considered as first time if the patient had not received a prescription for the same drug within the last 2 years. Patients who had not received a prescription for an antidepressant within 6 months prior to the date of redemption were classified as treatment-naïve. We included 82,702 first-time prescriptions, 65,313 (79 %) of which were for treatment-naïve patients. Of the treatment-naïve patients, 19 % were initially prescribed escitalopram. Hospital physicians prescribed escitalopram to 34 % of their treatment-naïve patients, while practitioners specialized in psychiatry prescribed it to 25 %, and general practitioners prescribed it to 17 %. General practitioners, however, were responsible for initiating 87 % of all treatment-naïve patients. The most expensive SSRI, escitalopram, is prescribed as first choice to one in five patients receiving their first antidepressant of escitalopram, citalopram or sertraline. General practitioners made the bulk of all first-time SSRI prescriptions to treatment-naïve patients.

SSRI effects on pyschomotor performance: assessment of citalopram and escitalopram on normal subjects.

PubMed

Paul, Michel A; Gray, Gary W; Love, Ryan J; Lange, Marvin

2007-07-01

Standard aeromedical doctrine dictates that aircrew receiving treatment for depression are grounded during treatment and follow-up observation, generally amounting to at least 1 yr. The Canadian Forces has initiated a program to return selected aircrew being treated for depression to restricted flying duties once stabilized on an approved antidepressant with resolution of depression. The currently approved medications are sertraline (a selective serotonin reuptake inhibitor) and bupropion (noradrenaline and dopamine reuptake inhibitor). This study was undertaken to determine whether or not citalopram or escitalopram affect psychomotor performance. In a double-blind crossover protocol with counter-balanced treatment order, 24 normal volunteer subjects (14 men and 10 women) were assessed for psychomotor performance during placebo, citalopram (40 mg), and escitalopram (20 mg) treatment. Each treatment arm lasted 2 wk, involving a daily morning ingestion of one capsule. There was a 1-wk washout period between medication courses. Subjects completed a drug side-effect questionnaire and were tested on three psychomotor test batteries once per week. Neither citalopram nor escitalopram affected serial reaction time, logical reasoning, serial subtraction, multitask, or MacWorth clock task performance. While we found some of the expected side effects due to citalopram and escitalopram, there was no impact on psychomotor performance. These findings support the possibility of using citalopram and escitalopram for returning aircrew to restricted flight duties (non-tactical flying) under close observation as a maintenance treatment after full resolution of depression.

Improvement of quality of life in panic disorder with escitalopram, citalopram, or placebo.

PubMed

Bandelow, B; Stein, D J; Dolberg, O T; Andersen, H F; Baldwin, D S

2007-07-01

It has been argued that measurement of outcome in panic disorder should not be limited to monitoring the number of panic attacks, but should include all domains that affect patient quality of life. Data from a randomized prospective comparison of escitalopram, citalopram, and placebo in patients with DSM-IV panic disorder were analyzed with regard to measurements of impairment of quality of life. The subscales of the Panic and Agoraphobia Scale (P&A) (Panic Attacks, Agoraphobic Avoidance, Anticipatory Anxiety, Functional and Social Disability, and Worries about Health) and the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) were analyzed. Treatment with escitalopram was associated with significant improvement on all 5 subscales of the P&A. Citalopram was significantly different from placebo in 3 subscales. Escitalopram and citalopram were significantly better than placebo in improving quality of life (measured by the total score of the Q-LES-Q Scale). Escitalopram was superior to placebo on 12 of 16 items of the Q-LES-Q, while citalopram was superior on 7 items. The P&A scale was more robust than measurement of panic frequency in differentiating medication from placebo. Escitalopram treatment was associated with improvement on all assessed domains that impair quality of life in panic disorder. Measurement of clinical improvement should not be solely based on panic attack frequency, but should also include assessment of a broad range of domains that affect patient quality of life.

A Danish cost-effectiveness model of escitalopram in comparison with citalopram and venlafaxine as first-line treatments for major depressive disorder in primary care.

PubMed

Sørensen, Jan; Stage, Kurt B; Damsbo, Niels; Le Lay, Agathe; Hemels, Michiel E

2007-01-01

The objective of this study was to model the cost-effectiveness of escitalopram in comparison with generic citalopram and venlafaxine in primary care treatment of major depressive disorder (baseline scores 22-40 on the Montgomery-Asberg Depression Rating Scale, MADRS) in Denmark. A three-path decision analytic model with a 6-month horizon was used. All patients started at the primary care path and were referred to outpatient or inpatient secondary care in the case of insufficient response to treatment. Model inputs included drug-specific probabilities derived from systematic literature review, ad-hoc survey and expert opinion. Main outcome measures were remission defined as MADRS < or = 12 and treatment costs. Analyses were conducted from healthcare system and societal perspectives. The human capital approach was used to estimate societal cost of lost productivity. Costs were reported in 2004 DDK. The expected overall 6-month remission rate was higher for escitalopram (64.1%) than citalopram (58.9%). From both perspectives, the total expected cost per successfully treated patient was lower for escitalopram (DKK 22,323 healthcare, DKK 72,399 societal) than for citalopram (DKK 25,778 healthcare, DKK 87,786 societal). Remission rates and costs were similar for escitalopram and venlafaxine. Robustness of the findings was verified in multivariate sensitivity analyses. For patients in primary care, escitalopram appears to be a cost-effective alternative to (generic) citalopram, with greater clinical benefit and cost-savings, and similar in cost-effectiveness to venlafaxine.

Treating Depression to Remission in Older Adults: A Controlled Evaluation of Combined Escitalopram with Interpersonal Psychotherapy versus Escitalopram with Depression Care Management

PubMed Central

Reynolds, Charles F.; Dew, Mary Amanda; Martire, Lynn M.; Miller, Mark D.; Cyranowski, Jill M.; Lenze, Eric; Whyte, Ellen M.; Mulsant, Benoit H.; Pollock, Bruce G.; Karp, Jordan F.; Gildengers, Ariel; Szanto, Katalin; Dombrovski, Alexandre Y.; Andreescu, Carmen; Butters, Meryl A.; Morse, Jennifer Q.; Houck, Patricia R.; Bensasi, Salem; Mazumdar, Sati; Stack, Jacqueline A.; Frank, Ellen

2010-01-01

Objective More than half of older adults respond only partially to first-line antidepressant pharmacotherapy. Our objective was to test the hypothesis that a depression-specific psychotherapy, Interpersonal Psychotherapy—IPT, when used adjunctively with escitalopram, would lead to a higher rate of remission and faster resolution of symptoms in partial responders than escitalopram with depression care management (DCM). Method We conducted a 16-week randomized clinical trial of IPT and DCM in partial responders to escitalopram, enrolling 124 outpatients aged 60 and older. The primary outcome, remission, was defined as three consecutive weekly scores of ≤7 on the Hamilton Rating Scale for Depression (17-item). We conducted Cox regression analyses of time to remission and logistic modeling for rates of remission. We tested group differences in Hamilton depression ratings over time via mixed-effects modeling. Results Remission rates for escitalopram with IPT and with DCM were similar in intention-to-treat (IPT versus DCM: 58 [95% CI: 46, 71] versus 45% [33,58]; p = 0.14) and completer analyses (IPT versus DCM: 58% [95% CI: 44,72] versus 43% [30, 57]; p = 0.20). Rapidity of symptom improvement did not differ in the two treatments. Conclusion No added advantage of IPT over DCM was shown. Depression care management is a clinically useful strategy to achieve full remission in about 50% of partial responders. PMID:20957693

Efficacy of early administration of escitalopram on depressive and emotional symptoms and neurological dysfunction after stroke: a multicentre, double-blind, randomised, placebo-controlled study.

PubMed

Kim, Jong S; Lee, Eun-Jae; Chang, Dae-Il; Park, Jong-Ho; Ahn, Seong Hwan; Cha, Jae-Kwan; Heo, Ji Hoe; Sohn, Sung-Il; Lee, Byung-Chul; Kim, Dong-Eog; Kim, Hahn Young; Kim, Seongheon; Kwon, Do-Young; Kim, Jei; Seo, Woo-Keun; Lee, Jun; Park, Sang-Won; Koh, Seong-Ho; Kim, Jin Young; Choi-Kwon, Smi

2017-01-01

Mood and emotional disturbances are common in patients with stroke, and adversely affect the clinical outcome. We aimed to evaluate the efficacy of early administration of escitalopram to reduce moderate or severe depressive symptoms and improve emotional and neurological dysfunction in patients with stroke. This was a placebo controlled, double-blind trial done at 17 centres in South Korea. Patients who had had an acute stroke within the past 21 days were randomly assigned in a 1:1 ratio to receive oral escitalopram (10 mg/day) or placebo for 3 months. Randomisation was done with permuted blocks stratified by centre, via a web-based system. The primary endpoint was the frequency of moderate or severe depressive symptoms (Montgomery-Åsberg Depression Rating Scale [MADRS] ≥16). Endpoints were assessed at 3 months after randomisation in the full analysis set (patients who took study medication and underwent assessment of primary endpoint after randomisation), in all patients who were enrolled and randomly assigned (intention to treat), and in all patients who completed the trial (per-protocol analysis). This trial is registered with ClinicalTrials.gov, number NCT01278498. Between Jan 27, 2011, and June 30, 2014, 478 patients were assigned to placebo (n=237) or escitalopram (n=241); 405 were included in the full analysis set (195 in the placebo group, 210 in the escitalopram group). The primary outcome did not differ by study group in the full analysis set (25 [13%] patients in the placebo group vs 27 [13%] in the escitalopram group; odds ratio [OR] 1·00, 95% CI 0·56-1·80; p>0·99) or in the intention-to-treat analysis (34 [14%] vs 35 [15%]; OR 1·01, 95% CI 0·61-1·69, p=0·96). The study medication was generally well tolerated; the most common adverse events were constipation (14 [6%] patients who received placebo vs 14 [6%] who received escitalopram), muscle pain (16 [7%] vs ten [4%]), and insomnia (12 [5%] vs 12 [5%]). Diarrhoea was more common in the escitalopram group (nine [4%] patients) than in the placebo group (two [1%] patients). Escitalopram did not significantly reduce moderate or severe depressive symptoms in patients with acute stroke. Dong-A Pharmaceutical and Ministry for Health, Welfare, and Family Affairs, South Korea. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sexual Pain among Malaysian Women Receiving Antidepressant: A Comparison between Escitalopram and Fluoxetine.

PubMed

Sidi, Hatta; Asmidar, Duni; Seng, Loh Huai; Jaafar, Nik Ruzyanei Nik; Midi, Marhani; Guan, Ng Chong

2016-03-01

The current study compares the risk of sexual pain in depressed female patients in remission between those who were treated with Escitalopram and Fluoxetine. The associated factors were also examined. This is a cross-sectional study involved 112 depressed female patients (56 treated with Escitalopram and 56 treated with Fluoxetine) who were in remission (as defined by Diagnostic and Statistical Manual-IV (DSM-IV) in the past 2 months and Montgomery-Asberg Depression Rating Scale (MADRS) score of ≤ 10) from the psychiatric clinic, University Kebangsaan Malaysia Medical Centre (UKMMC). They were interviewed using Structured Clinical Interview for DSM-IV (SCID). Hypoactive sexual desire was assessed using the Pain subscale of Malay Version of the Female Sexual Function Index (MVFSFI). The results show that risk of sexual pain was relatively low (16.07% for all patients), with no statistical significant between the two groups (17.86% for fluoxetine group, 14.29% for escitalopram group). Older age (adjusted odds ratio = 1.524, 95% CI = 1.199, 1.938) was the only factor significantly associated with sexual pain disorder. There should not be any barrier when continuing the use of escitalopram or fluoxetine as antidepressants amongst the female patients.

The effect of bupropion XL and escitalopram on memory and functional outcomes in adults with major depressive disorder: results from a randomized controlled trial.

PubMed

Soczynska, Joanna K; Ravindran, Lakshmi N; Styra, Rima; McIntyre, Roger S; Cyriac, Anna; Manierka, Marena S; Kennedy, Sidney H

2014-12-15

Decrements in cognitive function are a common feature of Major Depressive Disorder (MDD), and whether distinct classes of antidepressants differentially affect memory in these individuals has not been sufficiently evaluated. In this study we sought to determine the effect of escitalopram and bupropion XL on memory and psychosocial function. Forty-one individuals (18-50 years) with MDD were enrolled in an 8-week, double-blind, double-dummy, randomized controlled comparative trial of bupropion XL and escitalopram. Thirty-six participants completed pre and post memory assessments. Verbal, non-verbal and working memory were evaluated with a comprehensive neuropsychological battery. Psychosocial function was assessed with the Sheehan Disability Scale and Endicott Work Productivity Scale. Escitalopram and bupropion XL significantly improved immediate as well as delayed verbal and nonverbal memory, global function (all p≤0.001), and work productivity (p=0.045), with no significant between-group differences. Improvement in immediate verbal memory exerted a direct influence on improvement in global function (p=0.006). Treatment with either escitalopram or bupropion XL was associated with improvement in memory and psychosocial function in adults with MDD. Copyright © 2014. Published by Elsevier Ireland Ltd.

Effect of chronic escitalopram versus placebo on personality traits in healthy first-degree relatives of patients with depression: a randomized trial.

PubMed

Knorr, Ulla; Vinberg, Maj; Mortensen, Erik Lykke; Winkel, Per; Gluud, Christian; Wetterslev, Jørn; Gether, Ulrik; Kessing, Lars Vedel

2012-01-01

The serotonergic neurotransmitter system is closely linked to depression and personality traits. It is not known if selective serotonin reuptake inhibitors (SSRI) have an effect on neuroticism that is independent of their effect on depression. Healthy individuals with a genetic liability for depression represent a group of particular interest when investigating if intervention with SSRIs affects personality. The present trial is the first to test the hypothesis that escitalopram may reduce neuroticism in healthy first-degree relatives of patients with major depressive disorder (MD). The trial used a randomized, blinded, placebo-controlled parallel-group design. We examined the effect of four weeks escitalopram 10 mg daily versus matching placebo on personality in 80 people who had a biological parent or sibling with a history of MD. The outcome measure on personality traits was change in self-reported neuroticism scores on the Revised Neuroticism-Extroversion-Openness-Personality Inventory (NEO-PI-R) and the Eysenck Personality Inventory (EPQ) from entry until end of four weeks of intervention. When compared with placebo, escitalopram did not significantly affect self-reported NEO-PI-R and EPQ neuroticism and extroversion, EPQ psychoticism, NEO-PI-R openness, or NEO-PI-R conscientiousness (p all above 0.05). However, escitalopram increased NEO-PI-R agreeableness scores significantly compared with placebo (mean; SD) (2.38; 8.09) versus (-1.32; 7.94), p = 0.046), but not following correction for multiplicity. A trend was shown for increased conscientiousness (p = 0.07). There was no significant effect on subclinical depressive symptoms (p = 0.6). In healthy first-degree relatives of patients with MD, there is no effect of escitalopram on neuroticism, but it is possible that escitalopram may increase the personality traits of agreeableness and conscientiousness. Clinicaltrials.gov NCT00386841.

Escitalopram alters gene expression and HPA axis reactivity in rats following chronic overexpression of corticotropin-releasing factor from the central amygdala

PubMed Central

Flandreau, Elizabeth I.; Bourke, Chase H.; Ressler, Kerry J.; Vale, Wylie W.; Nemeroff, Charles B.; Owens, Michael J.

2013-01-01

Summary We have previously demonstrated that viral-mediated overexpression of corticotropin-releasing factor (CRF) within the central nucleus of the amygdala (CeA) reproduces many of the behavioral and endocrine consequences of chronic stress. The present experiment sought to determine whether administration of the selective serotonin reuptake inhibitor (SSRI) escitalopram reverses the adverse effects of CeA CRF overexpression. In a 2 × 2 design, adult male rats received bilateral infusions of a control lentivirus or a lentivirus in which a portion of the CRF promoter is used to drive increased expression of CRF peptide. Four weeks later, rats were then implanted with an Alzet minipump to deliver vehicle or 10 mg/kg/day escitalopram for a 4-week period of time. The defensive withdrawal (DW) test of anxiety and the sucrose-preference test (SPT) of anhedonia were performed both before and after pump implantation. Additional post-implant behavioral tests included the elevated plus maze (EPM) and social interaction (SI) test. Following completion of behavioral testing, the dexamethasone/CRF test was performed to assess HPA axis reactivity. Brains were collected and expression of HPA axis-relevant transcripts were measured using in situ hybridization. Amygdalar CRF overexpression increased anxiety-like behavior in the DW test at week eight, which was only partially prevented by escitalopram. In both CRF-overexpressing and control groups, escitalopram decreased hippocampal CRF expression while increasing hypothalamic and hippocampal expression of the glucocorticoid receptor (GR). These gene expression changes were associated with a significant decrease in HPA axis reactivity in rats treated with escitalopram. Interestingly, escitalopram increased the rate of weight gain only in rats overexpressing CRF. Overall these data support our hypothesis that amygdalar CRF is critical in anxiety-like behavior; because the antidepressant was unable to reverse behavioral manifestations of CeA CRF-OE. This may be a potential animal model to study treatment-resistant psychopathologies. PMID:23267723

Estimation of the optimal dosing regimen of escitalopram in dogs: A dose occupancy study with [11C]DASB

PubMed Central

Polis, Ingeborgh; Dockx, Robrecht; Vlerick, Lise; Dobbeleir, Andre; Goethals, Ingeborg; Saunders, Jimmy; Sadones, Nele; Baeken, Chris; De Vos, Filip; Peremans, Kathelijne

2017-01-01

Although the favourable characteristics of escitalopram as being the most selective serotonin reuptake inhibitor and having an increased therapeutic efficacy via binding on an additional allosteric binding site of the serotonin transporter, its dosing regimen has not yet been optimized for its use in dogs. This study aimed to estimate the optimal dosing frequency and the required dose for achieving 80% occupancy of the serotonin transporters in the basal ganglia. The dosing frequency was investigated by determining the elimination half-life after a four day oral pre-treatment period with 0.83 mg/kg escitalopram (3 administrations/day) and a subsequent i.v. injection 0.83 mg/kg. Blood samples were taken up to 12 hours after i.v. injection and the concentration of escitalopram in plasma was analysed via LC-MSMS. The dose-occupancy relationship was then determined by performing two PET scans in five adult beagles: a baseline PET scan and a second scan after steady state conditions were achieved following oral treatment with a specific dose of escitalopram ranging from 0.5 to 2.5 mg/kg/day. As the elimination half-life was determined to be 6.7 hours a dosing frequency of three administrations a day was proposed for the second part of the study. Further it was opted for a treatment period of four days, which well exceeded the minimum period to achieve steady state conditions. The optimal dosing regimen to achieve 80% occupancy in the basal ganglia and elicit a therapeutic effect, was calculated to be 1.85 mg/kg/day, divided over three administrations. Under several circumstances, such as insufficient response to other SSRIs, concurrent drug intake or in research studies focused on SERT, the use of escitalopram can be preferred over the use of the already for veterinary use registered fluoxetine, however, in case of long-term treatment with escitalopram, regularly cardiac screening is recommended. PMID:28644875

Estimation of the optimal dosing regimen of escitalopram in dogs: A dose occupancy study with [11C]DASB.

PubMed

Taylor, Olivia; Van Laeken, Nick; Polis, Ingeborgh; Dockx, Robrecht; Vlerick, Lise; Dobbeleir, Andre; Goethals, Ingeborg; Saunders, Jimmy; Sadones, Nele; Baeken, Chris; De Vos, Filip; Peremans, Kathelijne

2017-01-01

Although the favourable characteristics of escitalopram as being the most selective serotonin reuptake inhibitor and having an increased therapeutic efficacy via binding on an additional allosteric binding site of the serotonin transporter, its dosing regimen has not yet been optimized for its use in dogs. This study aimed to estimate the optimal dosing frequency and the required dose for achieving 80% occupancy of the serotonin transporters in the basal ganglia. The dosing frequency was investigated by determining the elimination half-life after a four day oral pre-treatment period with 0.83 mg/kg escitalopram (3 administrations/day) and a subsequent i.v. injection 0.83 mg/kg. Blood samples were taken up to 12 hours after i.v. injection and the concentration of escitalopram in plasma was analysed via LC-MSMS. The dose-occupancy relationship was then determined by performing two PET scans in five adult beagles: a baseline PET scan and a second scan after steady state conditions were achieved following oral treatment with a specific dose of escitalopram ranging from 0.5 to 2.5 mg/kg/day. As the elimination half-life was determined to be 6.7 hours a dosing frequency of three administrations a day was proposed for the second part of the study. Further it was opted for a treatment period of four days, which well exceeded the minimum period to achieve steady state conditions. The optimal dosing regimen to achieve 80% occupancy in the basal ganglia and elicit a therapeutic effect, was calculated to be 1.85 mg/kg/day, divided over three administrations. Under several circumstances, such as insufficient response to other SSRIs, concurrent drug intake or in research studies focused on SERT, the use of escitalopram can be preferred over the use of the already for veterinary use registered fluoxetine, however, in case of long-term treatment with escitalopram, regularly cardiac screening is recommended.

Effect of Chronic Escitalopram versus Placebo on Personality Traits in Healthy First-Degree Relatives of Patients with Depression: A Randomized Trial

PubMed Central

Knorr, Ulla; Vinberg, Maj; Mortensen, Erik Lykke; Winkel, Per; Gluud, Christian; Wetterslev, Jørn; Gether, Ulrik; Kessing, Lars Vedel

2012-01-01

Introduction The serotonergic neurotransmitter system is closely linked to depression and personality traits. It is not known if selective serotonin reuptake inhibitors (SSRI) have an effect on neuroticism that is independent of their effect on depression. Healthy individuals with a genetic liability for depression represent a group of particular interest when investigating if intervention with SSRIs affects personality. The present trial is the first to test the hypothesis that escitalopram may reduce neuroticism in healthy first-degree relatives of patients with major depressive disorder (MD). Methods The trial used a randomized, blinded, placebo-controlled parallel-group design. We examined the effect of four weeks escitalopram 10 mg daily versus matching placebo on personality in 80 people who had a biological parent or sibling with a history of MD. The outcome measure on personality traits was change in self-reported neuroticism scores on the Revised Neuroticism-Extroversion-Openness-Personality Inventory (NEO-PI-R) and the Eysenck Personality Inventory (EPQ) from entry until end of four weeks of intervention. Results When compared with placebo, escitalopram did not significantly affect self-reported NEO-PI-R and EPQ neuroticism and extroversion, EPQ psychoticism, NEO-PI-R openness, or NEO-PI-R conscientiousness (p all above 0.05). However, escitalopram increased NEO-PI-R agreeableness scores significantly compared with placebo (mean; SD) (2.38; 8.09) versus (−1.32; 7.94), p = 0.046), but not following correction for multiplicity. A trend was shown for increased conscientiousness (p = 0.07). There was no significant effect on subclinical depressive symptoms (p = 0.6). Conclusion In healthy first-degree relatives of patients with MD, there is no effect of escitalopram on neuroticism, but it is possible that escitalopram may increase the personality traits of agreeableness and conscientiousness. Trial Registration Clinicaltrials.gov NCT00386841 PMID:22393376

Reduced effectiveness of escitalopram in the forced swimming test is associated with increased serotonin clearance rate in food restricted rats

PubMed Central

France, CP; Li, J-X; Owens, WA; Koek, W; Toney, GM; Daws, LC

2012-01-01

Efficacy of antidepressant drugs is often limited. One of the limiting factors may be diet. This study shows that the effect of escitalopram in the forced swimming test is diminished in rats by food restriction that decreased body weight by 8%. The primary target for escitalopram is the serotonin (5-HT) transporter. Using high-speed chronoamperometry to measure 5-HT clearance in vivo in rats fed the same food restricted diet, the rate of 5-HT clearance from extracellular fluid in brain was dramatically increased. Increased 5-HT transporter function under conditions of dietary restriction might contribute to the decreased effect of escitalopram. These results suggest that diet plays an integral role in determining efficacy of antidepressant drugs, and might well generalize to other psychoactive drugs that impinge upon the 5-HT transporter. PMID:19419596

The use of statins for the treatment of depression in patients with acute coronary syndrome

PubMed Central

Kim, S W; Bae, K Y; Kim, J M; Shin, I S; Hong, Y J; Ahn, Y; Jeong, M H; Berk, M; Yoon, J S

2015-01-01

This study aimed to investigate the effect of statins for the treatment of depression in individuals with acute coronary syndrome (ACS). We used 1-year follow-up data of a 24-week double-blind, placebo-controlled trial of escitalopram and a naturalistic prospective observational cohort study. Of 446 participants with comorbid depressive disorders and ACS at baseline, 300 participated in a randomised escitalopram trial and the remaining 146 participated in a naturalistic observational study. The participants in the two studies were approached for a 1-year follow-up investigation. Treatment response rates, defined as a ⩾50% reduction in the Hamilton Depression Rating Scale (HAM-D) and Beck Depression Inventory (BDI) scores, were used as the outcome variables. In the escitalopram trial, both HAM-D and BDI response rates were highest in patients taking escitalopram and statins together and lowest in patients receiving neither medication. Logistic regression analyses revealed that statin use was significantly associated with higher response rates on both the HAM-D and BDI at 1 year, whereas no such associations were found for escitalopram. In the naturalistic observational study, the response rates at 1 year did not differ significantly by statin use. Instead, the HAM-D response rate was significantly higher in patients taking lipophilic statins than in those who did not. In conclusion, statins may be effective for the treatment of depression independent of medical status and escitalopram use, and they may potentiate the antidepressant action of serotonergic antidepressants in patients with ACS. PMID:26285130

In Vivo Investigation of Escitalopram’s Allosteric Site on the Serotonin Transporter

PubMed Central

Murray, Karen E.; Ressler, Kerry J.; Owens, Michael J.

2015-01-01

Escitalopram is a commonly prescribed antidepressant of the selective serotonin reuptake inhibitor class. Clinical evidence and mapping of the serotonin transporter (SERT) identified that escitalopram, in addition to its binding to a primary uptake-blocking site, is capable of binding to the SERT via an allosteric site that is hypothesized to alter escitalopram’s kinetics at the SERT. The studies reported here examined the in vivo role of the SERT allosteric site in escitalopram action. A knockin mouse model that possesses an allosteric-null SERT was developed. Autoradiographic studies indicated that the knockin protein was expressed at a lower density than endogenous mouse SERT (approximately 10–30% of endogenous mouse SERT), but the knockin mice are a viable tool to study the allosteric site. Microdialysis studies in the ventral hippocampus found no measurable decrease in extracellular serotonin response after local escitalopram challenge in mice without the allosteric site compared to mice with the site (p = 0.297). In marble burying assays there was a modest effect of the absence of the allosteric site, with a larger systemic dose of escitalopram (10-fold) necessary for the same effect as in mice with intact SERT (p = 0.023). However, there was no effect of the allosteric site in the tail suspension test. Together these data suggest that there may be a regional specificity in the role of the allosteric site. The lack of a robust effect overall suggests that the role of the allosteric site for escitalopram on the SERT may not produce meaningful in vivo effects. PMID:26621784

Prenatal exposure to escitalopram and/or stress in rats: a prenatal stress model of maternal depression and its treatment

PubMed Central

Bourke, Chase H.; Capello, Catherine F.; Rogers, Swati M.; Yu, Megan L.; Boss-Williams, Katherine A.; Weiss, Jay M.; Stowe, Zachary N.; Owens, Michael J.

2014-01-01

Rationale A rigorously investigated model of stress and antidepressant administration during pregnancy is needed to evaluate possible effects on the mother. Objective The objective of this study was to develop a model of clinically relevant prenatal exposure to an antidepressant and stress during pregnancy to evaluate the effects on maternal care behavior. Results Female rats implanted with 28 day osmotic minipumps delivering the SSRI escitalopram throughout pregnancy had serum escitalopram concentrations in a clinically observed range (17-65 ng/mL). A separate cohort of pregnant females exposed to a chronic unpredictable mild stress paradigm on gestational days 10-20 showed elevated baseline (305 ng/mL), and acute stress-induced (463 ng/mL), plasma corticosterone concentrations compared to unstressed controls (109 ng/mL). A final cohort of pregnant dams were exposed to saline (control), escitalopram, stress, or stress and escitalopram to determine the effects on maternal care. Maternal behavior was continuously monitored over the first 10 days post parturition. A reduction of 35% in maternal contact and 11% in nursing behavior was observed due to stress during the light cycle. Licking and grooming behavior was unaffected by stress or drug exposure in either the light or dark cycle. Conclusions These data indicate that: 1) clinically relevant antidepressant treatment during human pregnancy can be modeled in rats using escitalopram; 2) chronic mild stress can be delivered in a manner that does not compromise fetal viability; and 3) neither of these prenatal treatments substantially altered maternal care post parturition. PMID:23436130

Adrenal activity and metabolic risk during randomized escitalopram or placebo treatment in PCOS.

PubMed

Glintborg, Dorte; Altinok, Magda Lambaa; Ravn, Pernille; Stage, Kurt Bjerregaard; Højlund, Kurt; Andersen, Marianne

2018-03-01

Polycystic ovary syndrome (PCOS) is associated with insulin resistance, adrenal hyperactivity and decreased mental health. We aimed to investigate the changes in adrenal activity, metabolic status and mental health in PCOS during treatment with escitalopram or placebo. Forty-two overweight premenopausal women with PCOS and no clinical depression were randomized to 12-week SSRI (20 mg escitalopram/day, n  = 21) or placebo ( n  = 21). Patients underwent clinical examination, fasting blood samples, adrenocorticotroph hormone (ACTH) test, 3-h oral glucose tolerance test (OGTT) and filled in questionnaires regarding mental health and health-related quality of life (HRQoL): WHO Well-Being Index (WHO-5), Major Depression Inventory (MDI), Short Form 36 (SF-36) and PCOS questionnaire. Included women were aged 31 (6) years (mean (s.d.)) and had body mass index (BMI) 35.8 (6.5) kg/m 2 and waist 102 (12) cm. Escitalopram was associated with increased waist (median (quartiles) change 1 (0; 3) cm), P  = 0.005 vs change during placebo and increased cortisol levels (cortisol 0, cortisol 60, peak cortisol and area under the curve for cortisol during ACTH test), all P   <  0.05 vs changes during placebo. Escitalopram had no significant effect on measures of insulin sensitivity, insulin secretion, fasting lipids, mental health or HRQoL. Waist circumference and cortisol levels increased during treatment with escitalopram in women with PCOS and no clinical depression, whereas metabolic risk markers, mental health and HRQol were unchanged. © 2018 The authors.

Blocking serotonin but not dopamine reuptake alters neural processing during perceptual decision making.

PubMed

Costa, Vincent D; Kakalios, Laura C; Averbeck, Bruno B

2016-10-01

Dopamine and serotonin have opponent interactions on aspects of impulsivity. Therefore we wanted to test the hypothesis that dopamine and serotonin would have opposing effects on speed-accuracy trade offs in a perceptual decision making task. Unlike other behavioral measures of impulsivity, perceptual decision making allows us to determine whether decreasing premature responses, often interpreted as decreased impulsivity, corresponds to increased behavioral performance. We administered GBR-12909 (a dopamine transporter blocker), escitalopram (a serotonin transporter blocker), or saline in separate sessions to 3 rhesus macaques. We found that animals had slower reaction times (RTs) on escitalopram than on GBR-12909 or saline. However, they were also least accurate on escitalopram. Animals were faster, although nonsignificantly, on GBR than saline and had equivalent accuracy. Administration of GBR-12909 did cause animals to be faster in error trials than correct trials. Therefore, from the point of view of RTs the animals were less impulsive on escitalopram. However, the decreased accuracy of the monkeys shows that they were not able to make use of their slower response times to make more accurate decisions. Therefore, impulsivity was reduced on escitalopram, but at the expense of a slower information-processing rate in the perceptual inference task. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Pharmacokinetics and effect on the corrected QT interval of single-dose escitalopram in healthy elderly compared with younger adults.

PubMed

Chung, Hyewon; Kim, Anhye; Lim, Kyoung Soo; Park, Sang-In; Yu, Kyung-Sang; Yoon, Seo Hyun; Cho, Joo-Youn; Chung, Jae-Yong

2017-01-01

Escitalopram is the (S)-enantiomer of citalopram that has a potential QT prolonging effect. In this study, 12 healthy elderly individuals received a single oral dose of escitalopram (20 mg), and their pharmacokinetics and QT effect data were compared with data from 33 younger adults obtained in a previous study. Serial blood samples for pharmacokinetic analysis were collected and ECG was performed up to 48 h postdose. The elderly and younger adults showed similar pharmacokinetic profiles. The geometric mean ratios (90% confidence interval) of the elderly compared with the younger adults were 1.02 (0.89-1.17) and 1.01 (0.86-1.17) for the maximum plasma concentration and area under the concentration-time curve, respectively. The mean baseline-adjusted QT (dQT) time profiles were similar and the mean values of maximum dQT were not significantly different between the elderly and the younger adults. The linear mixed-effect model indicated a weak but positive relationship between the escitalopram concentration and dQT, with an estimated coefficient of concentration of 0.43-0.54. In conclusion, the pharmacokinetics and QT effect of a single dose of escitalopram observed in the elderly without comorbidities and younger adults were generally similar.

Sexual arousal difficulties in women treated with antidepressants: a comparison between escitalopram and fluoxetine.

PubMed

Midi, Marhani; Kanagasundram, Sharmilla; Sidi, Hatta; Asmidar, Duni; Naing, Ling; Guan, Ng Chong

2012-01-01

To compare the risk of sexual arousal difficulties between two groups of depressed female patients in remission who were treated with either escitalopram or fluoxetine. Associated factors were also examined. This was a cross-sectional study involving 112 female patients attending the psychiatric clinic, University Kebangsaan Malaysia Medical Centre (UKMMC) with depressive disorders as assessed by using the Structured Clinical Interview for DSM-IV (SCID), who had been in remission for the previous 2 months as defined by a score of < or = 10 from an assessment using the Montgomery-Asberg Depression Rating Scale (MADRS) and were treated with either fluoxetine or escitalopram. Sexual arousal difficulties were assessed using the arousal subscale of Malay Version of the Female Sexual Function Index (MVFSFI). The rate of sexual arousal difficulties was 41.1% for all subjects. Sexual arousal difficulties occurred in 50.0% of subjects treated with fluoxetine and 32.1% with escitalopram. However, this difference was not statistically significant (p = 0.055). Multivariate logistic regression analysis showed that higher dose of antidepressant (adjusted OR = 4.08, 95 CI = 1.70-9.81) was significantly associated with female sexual arousal difficulties. The risk of sexual arousal difficulties was higher in female patients who were treated with higher doses of either fluoxetine or escitalopram.

Sexual Pain among Malaysian Women Receiving Antidepressant: A Comparison between Escitalopram and Fluoxetine

PubMed Central

Sidi, Hatta; Asmidar, Duni; Seng, Loh Huai; Jaafar, Nik Ruzyanei Nik; Midi, Marhani; Guan, Ng Chong

2016-01-01

Objectives The current study compares the risk of sexual pain in depressed female patients in remission between those who were treated with Escitalopram and Fluoxetine. The associated factors were also examined. Methods This is a cross-sectional study involved 112 depressed female patients (56 treated with Escitalopram and 56 treated with Fluoxetine) who were in remission (as defined by Diagnostic and Statistical Manual-IV (DSM-IV) in the past 2 months and Montgomery-Asberg Depression Rating Scale (MADRS) score of ≤ 10) from the psychiatric clinic, University Kebangsaan Malaysia Medical Centre (UKMMC). They were interviewed using Structured Clinical Interview for DSM-IV (SCID). Hypoactive sexual desire was assessed using the Pain subscale of Malay Version of the Female Sexual Function Index (MVFSFI). Results The results show that risk of sexual pain was relatively low (16.07% for all patients), with no statistical significant between the two groups (17.86% for fluoxetine group, 14.29% for escitalopram group). Older age (adjusted odds ratio = 1.524, 95% CI = 1.199, 1.938) was the only factor significantly associated with sexual pain disorder. Conclusions There should not be any barrier when continuing the use of escitalopram or fluoxetine as antidepressants amongst the female patients. PMID:27738371

Impact of acute administration of escitalopram on the processing of emotional and neutral images: a randomized crossover fMRI study of healthy women.

PubMed

Outhred, Tim; Das, Pritha; Felmingham, Kim L; Bryant, Richard A; Nathan, Pradeep J; Malhi, Gin S; Kemp, Andrew H

2014-07-01

Acute neural effects of antidepressant medication on emotion processing biases may provide the foundation on which clinical outcomes are based. Along with effects on positive and negative stimuli, acute effects on neutral stimuli may also relate to antidepressant efficacy, yet these effects are still to be investigated. The present study therefore examined the impact of a single dose of the selective serotonin reuptake inhibitor escitalopram (20 mg) on positive, negative and neutral stimuli using pharmaco-fMRI. Within a double-blind, randomized, placebo-controlled crossover design, healthy women completed 2 sessions of treatment administration and fMRI scanning separated by a 1-week washout period. We enrolled 36 women in our study. When participants were administered escitalopram relative to placebo, left amygdala activity was increased and right inferior frontal gyrus (IFG) activity was decreased during presentation of positive pictures (potentiation of positive emotion processing). In contrast, escitalopram was associated with decreased left amygdala and increased right IFG activity during presentation of negative pictures (attenuation of negative emotion processing). In addition, escitalopram decreased right IFG activity during the processing of neutral stimuli, akin to the effects on positive stimuli (decrease in negative appraisal). Although we used a women-only sample to reduce heterogeneity, our results may not generalize to men. Potential unblinding, which was related to the subjective occurrence of side effects, occurred in the study; however, manipulation check analyses demonstrated that results were not impacted. These novel findings demonstrate that a single dose of the commonly prescribed escitalopram facilitates a positive information processing bias. These findings provide an important lead for better understanding effects of antidepressant medication.

Actual driving performance and psychomotor function in healthy subjects after acute and subchronic treatment with escitalopram, mirtazapine, and placebo: a crossover trial.

PubMed

Wingen, Marleen; Bothmer, John; Langer, Stefan; Ramaekers, Johannes G

2005-04-01

The effects of escitalopram 10 to 20 mg/day and mirtazapine 30 to 45 mg/day on actual driving and psychomotor performance of 18 healthy subjects were determined in a randomized, double-blind, placebo-controlled, multiple-dose, 3-way crossover trial. Each treatment period lasted for 15 days and was separated from the next period by a washout period of at least 13 days. Subjects received an evening dose of escitalopram 10 mg, mirtazapine 30 mg, or placebo from days 1 to 7 and an evening dose of escitalopram 20 mg, mirtazapine 45 mg, or placebo from days 8 to 15. On days 2, 9, and 16, reflecting acute period, dose increase, and steady state, respectively, the Road Tracking Test was performed. The main parameter was standard deviation of lateral position. Psychomotor performance was also assessed on days 2, 9, and 16 by laboratory computer tasks. Subjective sleep quality was measured with the Groninger Sleep Quality Scale, and mood was measured by visual analogue scales. Treatment differences were apparent during the acute treatment period, in which subjects treated with mirtazapine 30 mg performed less well on the driving test as compared to placebo. The Divided Attention Task results also revealed a significant increase in tracking error after a single dose of mirtazapine 30 mg as compared to placebo. Mirtazapine decreased feelings of alertness and contentedness. Mirtazapine did not affect performance on days 9 and 16 of treatment. Escitalopram did not affect driving, psychomotor performance, or subjective mood throughout treatment. Driving performance, as well as psychomotor functioning, was not affected by escitalopram treatment in healthy subjects. Driving performance was significantly impaired after ingestion of mirtazapine 30 mg during the acute treatment period.

Area-specific modulation of neural activation comparing escitalopram and citalopram revealed by pharmaco-fMRI: a randomized cross-over study.

PubMed

Windischberger, Christian; Lanzenberger, Rupert; Holik, Alexander; Spindelegger, Christoph; Stein, Patrycja; Moser, Ulrike; Gerstl, Florian; Fink, Martin; Moser, Ewald; Kasper, Siegfried

2010-01-15

Area-specific and stimulation-dependent changes of human brain activation by selective serotonin reuptake inhibitors (SSRI) are an important issue for improved understanding of treatment mechanisms, given the frequent prescription of these drugs in depression and anxiety disorders. The aim of this neuroimaging study was to investigate differences in BOLD-signal caused by administration of the SSRIs escitalopram and citalopram using pharmacological functional magnetic resonance imaging (pharmaco-fMRI). Eighteen healthy subjects participated in a placebo-controlled, randomized, double-blind study in cross-over repeated measures design. Each volunteer performed facial emotional discrimination and a sensorimotor control paradigm during three scanning sessions. Citalopram (20 mg/d), escitalopram (10 mg/d) and placebo were administered for 10 days each with a drug-free period of at least 21 days. Significant pharmacological effects on BOLD-signal were found in the amygdala, medial frontal gyrus, parahippocampal, fusiform and middle temporal gyri. Post-hoc t-tests revealed decreased BOLD-signal in the right amygdala and left parahippocampal gyrus in both pharmacological conditions, compared to placebo. Escitalopram, compared to citalopram, induced a decrease of BOLD-signal in the medial frontal gyrus and an increase in the right fusiform and left parahippocampal gyri. Drug effects were concentrated in brain regions with dense serotonergic projections. Both escitalopram and citalopram attenuated BOLD-signal in the amygdala and parahippocampal cortex to emotionally significant stimuli compared to control stimuli. We believe that reduced reactivity in the medial frontal gyrus found for escitalopram compared to citalopram administration might explain the response differences between study drugs as demonstrated in previous clinical trials.

Escitalopram plasma levels and antidepressant response.

PubMed

Florio, Vincenzo; Porcelli, Stefano; Saria, Alois; Serretti, Alessandro; Conca, Andreas

2017-09-01

Major Depression Disorder (MDD) has a highly variable treatment response due to the large inter-individual variation in the pharmacokinetics and pharmacodynamics of drug treatments. In detail the correlation between plasma level and efficacy has been much debated. Among first-line drugs for MDD, one of the most used is escitalopram. In the present study we investigated the association between serum concentration of escitalopram (SCE) and antidepressant response (AR). 70 MDD patients treated with escitalopram monotherapy were recruited and followed for three months. Hamilton Depression Rating Scale - 21 (HAMD-21) was administrated at baseline, month 1, and month 3 to assess AR. SCE was measured at steady state. Linear regression analysis and nonlinear least-squares regression were used to estimate association between SCE and AR. We found an association between SCE and AR both at month 1 (p<0.001) and month 3 (p=0.0003), which persists also excluding 3 patients with SCE equal to 0. Interestingly, by excluding patients with SCE < 20ng/mL, i.e. with a SCE lower than the putative therapeutic threshold, these associations disappeared. The curvilinear function AR = a + (SCE-SCE 2 ) explained a higher proportion of variance compared to the linear other models (p<0.001). Our results suggest that for escitalopram the association between SCE and AR likely follows a nearly-asymptotic function, with poor AR at sub-therapeutic SCE and stable AR response at therapeutic SCE. Thus, when a patient reaches the therapeutic SCE range, further increase of escitalopram dosage seems to be useless, although further studies are needed to confirm our findings. Copyright © 2017 Elsevier B.V. and ECNP. All rights reserved.

Can we well assess the relative efficacy and tolerability of a new drug versus others at the time of marketing authorization using mixed treatment comparisons? A detailed illustration with escitalopram.

PubMed

Llorca, Pierre-Michel; Lançon, Christophe; Brignone, Mélanie; Painchault, Caroline; Rive, Benoit; Toumi, Mondher; François, Clément

2015-01-01

To assess the variation of relative efficacy and tolerability of an antidepressant versus others based on both pre-marketing (registration studies) and post-marketing studies versus pre-marketing studies only in patients with major depressive disorder. The relative efficacy and tolerability of antidepressants was assessed by mixed treatment comparisons (MTCs) using data acquired over two time periods: before registration of the reference drug escitalopram (1989-2002) and up to 5 years later (1989-2007). Ranking probability outputs were presented for efficacy, using change from baseline to 8 weeks on Montgomery-Åsberg Depression Rating Scale total score, and tolerability, using withdrawals due to adverse events. The relative efficacy and tolerability of some selected antidepressants, including escitalopram, varied considerably over the two time periods. The improved relative efficacy and tolerability of escitalopram over time, compared with citalopram, was demonstrated by greater separation of ranking probability curves for efficacy and tolerability. In 2002, escitalopram ranked low with 13.9% and 5.1% probability of being in the top four antidepressants' relative efficacy and tolerability, respectively. In 2007, ranking probabilities for relative efficacy and tolerability of escitalopram increased to 52.5% and 82.1%, respectively. Time of marketing authorization may not be the most appropriate time to evaluate the relative efficacy and tolerability of a new antidepressant based on MTC approach due to the asymmetry of information between new and older compounds. However, the first evaluation of relative effect of a new drug for health technology assessment recommendations is commonly done at this time. Re-evaluation of a drug several years after its launch is likely to provide a more accurate indication of its relative efficacy and tolerability.

Economic consequence of switching to citalopram after its generic entry for adult patients with major depressive disorder (MDD) treated with escitalopram: a 6-month retrospective study.

PubMed

Yu, Andrew P; Xie, Jipan; Bensimon, Arielle; Parikh, Kejal; Wu, Eric Q; Ben-Hamadi, Rym; Blum, Steven; Haim Erder, M

2010-01-01

To estimate, from a third-party payer's perspective, the effects of switching from escitalopram to citalopram, after the generic entry of citalopram, on hospitalization and healthcare costs among adult MDD patients who were on escitalopram therapy. Adult MDD patients treated with escitalopram were identified from Ingenix Impact claims database. MDD- and mental health (MH)-related hospitalization rates and healthcare costs were compared between 'switchers' (patients who switched to citalopram after its generic entry) and 'non-switchers'. MDD- and MH-related outcomes were defined as having a primary or a secondary diagnosis of ICD-9-CM = 296.2x, 296.3x and ICD-9-CM = 290-319, respectively. A propensity score matching method that estimated the likelihood of switching using baseline characteristics was used. Outcomes were examined for both 3-month and 6-month post-index periods. The sample included 3,427 matched pairs with balanced baseline characteristics. Switchers were more likely to incur an MDD-related (odds ratio [OR] = 1.52) and MH-related hospitalization (OR = 1.34) during the 6-month post-index period (both p < 0.05). Compared to switchers, non-switchers had significantly lower MDD- and MH-related hospitalization costs ($248.3 and $219.8 lower, respectively) and medical costs ($277.4 and $246.4 lower, respectively) (all p < 0.05). Although non-switchers had significantly higher MDD- and MH-related prescription drug costs, overall they had significantly lower total MDD- and MH-related healthcare costs ($109.9 and $93.6 lower, respectively; both p < 0.001). The 3-month results were consistent with these 6-month findings. The study limitations included limited generalizability of study findings, inability to differentiate switching from escitalopram to citalopram due to medical reasons versus non-medical reasons, and exclusion of indirect costs from cost calculations. Compared to patients maintaining on escitalopram, switchers from escitalopram to citalopram experienced higher risk of MDD- and MH-related hospitalization and incurred higher total MDD- and MH-related healthcare costs. The economic consequences of therapeutic substitution should take into account total healthcare costs, not just drug acquisition costs.

Enantioselective analysis of citalopram and escitalopram in postmortem blood together with genotyping for CYP2D6 and CYP2C19.

PubMed

Carlsson, Björn; Holmgren, Anita; Ahlner, Johan; Bengtsson, Finn

2009-03-01

Citalopram is marketed as a racemate (50:50) mixture of the S(+)-enantiomer and R(-)-enantiomer and the active S(+)-enantiomer (escitalopram) that possess inhibitory effects. Citalopram was introduced in Sweden in 1992 and is the most frequently used antidepressant to date in Sweden. In 2002, escitalopram was introduced onto the Swedish market for treatment of depression and anxiety disorders. The main objective of this study was to investigate S(+)-citalopram [i.e., the racemic drug (citalopram) or the enantiomer (escitalopram)] present in forensic autopsy cases positive for the presence of citalopram in routine screening using a non-enantioselective bioanalytical method. Fifty out of the 270 samples found positive by gas chromatography-nitrogen-phosphorus detection were further analyzed using enantioselective high-performance liquid chromatography. The 50 cases were genotyped for CYP2D6 and CYP2C19, as these isoenzymes are implicated in the metabolism of citalopram and escitalopram. In samples positive for racemic citalopram using the screening method for forensic autopsy cases, up to 20% would have been misinterpreted in the absence of an enantioselective method. An enantioselective method is thus necessary for correct interpretation of autopsy cases, after the enantiomer has been introduced onto the market. The percentage of poor metabolizers was 6% for CYP2D6 and 8% for CYP2C19.

Differences in the dynamics of serotonin reuptake transporter occupancy may explain superior clinical efficacy of escitalopram versus citalopram.

PubMed

Kasper, Siegfried; Sacher, Julia; Klein, Nikolas; Mossaheb, Nilufar; Attarbaschi-Steiner, Trawat; Lanzenberger, Rupert; Spindelegger, Christoph; Asenbaum, Susanne; Holik, Alexander; Dudczak, Robert

2009-05-01

Escitalopram the S-enantiomer of the racemate citalopram, is clinically more effective than citalopram in the treatment of major depressive disorder. However, the precise mechanism by which escitalopram achieves superiority over citalopram is yet to be determined. It has been hypothesized that the therapeutically inactive R-enantiomer competes with the serotonin-enhancing S-enantiomer at a low-affinity allosteric site on serotonin reuptake transporters (SERTs), and reduces the effectiveness of the S-enantiomer at the primary, high-affinity serotonin-binding site. This study summarizes the results of two recent single-photon emission computerized tomography studies measuring SERT occupancy in citalopram-treated and escitalopram-treated healthy volunteers, after a single dose and multiple doses (i.e. under steady-state conditions). The single-dose study showed no attenuating effect of R-citalopram. After multiple dosing, however, SERT occupancy was significantly reduced in the presence of R-citalopram. Under steady-state conditions, R-enantiomer concentrations were greater than for the S-enantiomer because of slower clearance of R-citalopram. A pooled analysis suggests that build-up of the R-enantiomer after repeated citalopram dosing may lead to increased inhibition of S-enantiomer occupancy of SERT. This review adds to the growing body of evidence regarding differences in the dynamics of SERT occupancy, that is, molecular mechanisms underlying the often-observed superior clinical efficacy of escitalopram compared with citalopram in major depressive disorder.

Escitalopram in the Treatment of Adolescent Depression: A Randomized Placebo-Controlled Multisite Trial

ERIC Educational Resources Information Center

Emslie, Graham J.; Ventura, Daniel; Korotzer, Andrew; Tourkodimitris, Stavros

2009-01-01

A randomized, double-blind, placebo-controlled trial that involves 312 male and female patients aged 12-17 reveal the effectiveness of escitalopram in the treatment of depressed adolescents. Eighty-three percent of the participants or 259 participants completed the 8 weeks therapy period.

The dielectric signature of glass density

NASA Astrophysics Data System (ADS)

Rams-Baron, M.; Wojnarowska, Z.; Knapik-Kowalczuk, J.; Jurkiewicz, K.; Burian, A.; Wojtyniak, M.; Pionteck, J.; Jaworska, M.; Rodríguez-Tinoco, C.; Paluch, M.

2017-09-01

At present, we are witnessing a renewed interest in the properties of densified glasses prepared by isobaric cooling of a liquid at elevated pressure. As high-pressure densification emerges as a promising approach in the development of glasses with customized features, understanding and controlling their unique properties represent a contemporary scientific and technological goal. The results presented herein indicate that the applied high-pressure preparation route leads to a glassy state with higher density (˜1%) and a reduced free volume of about 7%. We show that these subtle structural changes remarkably influence the dielectric response and spectral features of β-relaxation in etoricoxib glass. Our study, combining dynamical and structural techniques, reveal that β-relaxation in etoricoxib is extremely sensitive to the variations in molecular packing and can be used to probe the changes in glass density. Such connection is technologically relevant and may advance further progress in the field.

Luteinized unruptured follicle syndrome increased by inactive disease and selective cyclooxygenase 2 inhibitors in women with inflammatory arthropathies.

PubMed

Micu, Mihaela C; Micu, Romeo; Ostensen, Monika

2011-09-01

Administration of nonsteroidal antiinflammatory drugs (NSAIDs) may impair fertility. The occurrence of the luteinized unruptured follicle (LUF) syndrome was assessed in women with inflammatory arthropathies exposed to NSAIDs and compared to that in nonexposed women. Fourteen patients with inflammatory rheumatic disease, 29 women with noninflammatory musculoskeletal conditions, and 449 women not exposed to NSAIDs were studied by intravaginal ultrasound monitoring for follicular development and ovulation in 1 or more menstrual cycles. Disease activity was assessed in inflammatory rheumatic disease. In 59 monitored cycles of patients with continuous NSAID exposure, 35.6% of LUF syndromes occurred compared to 3.4% of LUF syndromes in untreated women (P < 0.001). Etoricoxib was responsible for 75% of LUF syndromes in patients exposed continuously, whereas diclofenac generated 15% of LUF syndromes. An ibuprofen dosage of 1,600 mg/day did not induce LUF syndrome either at continuous periovulatory or discontinuous exposure. Interestingly, the frequency of LUF syndrome was 46.2% in patients with inactive inflammatory disease compared to 15% in patients with active disease (P = 0.023). Etoricoxib generated LUF syndrome in 94.2% of the cases with inactive disease versus 28.6% in patients with active disease (P = 0.003). NSAIDs increased the risk of the LUF syndrome, particularly in patients with inactive disease. The selective cyclooxygenase 2 (COX-2) inhibitor etoricoxib was a more potent inductor of LUF syndrome than nonselective COX inhibitors. Continuous periovulatory exposure to NSAIDs should be avoided when planning a pregnancy in patients with rheumatic diseases. Copyright © 2011 by the American College of Rheumatology.

Upregulation of intrinsic apoptotic pathway in NSAIDs mediated chemoprevention of experimental lung carcinogenesis.

PubMed

Setia, Shruti; Sanyal, Sankar N

2012-01-01

Non-steroidal anti-inflammatory drugs (NSAIDs) act by inhibition of cyclooxygenase-2 (COX-2), which is overexpressed in cancer. The role of COX-2 and apoptosis were evaluated in 9,10-dimethylbenz(a)anthracene (DMBA)-induced lung cancer in rat and chemoprevention with indomethacin, a traditional NSAID and etoricoxib, a selective COX-2 inhibitor. The animals were divided into Control, DMBA, DMBA+ indomethacin and DMBA+ etoricoxib groups. They received a single intratracheal instillation of DMBA while NSAIDs were given orally daily for 32 weeks. Besides morphology and histology of lungs, RT-PCR, western blots and immunohistochemistry were performed for the expression of apoptotic proteins and COX enzymes. Apoptosis was studied by DNA fragmentation and fluorescent staining. The occurrence of tumors and lesions was noted in the DMBA animals, besides constricted alveolar spaces and hyperplasia. COX-1 was found to be uniformly expressed while COX-2 level was raised significantly in DMBA group. The apoptotic proteins, apaf-1, caspase-9 and caspase-3 were highly diminished in DMBA group but restored to normal level in NSAIDs groups. Also, apoptosis was suppressed in carcinogen group by DNA fragmentation analysis and fluorescent staining of the lung cells while co-administration of NSAIDs along with DMBA led to the restoration of apoptosis. DMBA administration to the rats led to tumorigenesis in the lungs, had no effects on COX-1 expression, while elevating the COX-2 levels and suppressing apoptosis. The treatment with NSAIDs led to the amelioration of these effects. However, etoricoxib which is a COX-2 specific inhibitor, was found to be more effective than the traditional NSAID, indomethacin.

Executive functioning complaints and escitalopram treatment response in late-life depression.

PubMed

Manning, Kevin J; Alexopoulos, George S; Banerjee, Samprit; Morimoto, Sarah Shizuko; Seirup, Joanna K; Klimstra, Sibel A; Yuen, Genevieve; Kanellopoulos, Theodora; Gunning-Dixon, Faith

2015-05-01

Executive dysfunction may play a key role in the pathophysiology of late-life depression. Executive dysfunction can be assessed with cognitive tests and subjective report of difficulties with executive skills. The present study investigated the association between subjective report of executive functioning complaints and time to escitalopram treatment response in older adults with major depressive disorder (MDD). 100 older adults with MDD (58 with executive functioning complaints and 42 without executive functioning complaints) completed a 12-week trial of escitalopram. Treatment response over 12 weeks, as measured by repeated Hamilton Depression Rating Scale scores, was compared for adults with and without executive complaints using mixed-effects modeling. Mixed effects analysis revealed a significant group × time interaction, F(1, 523.34) = 6.00, p = 0.01. Depressed older adults who reported executive functioning complaints at baseline demonstrated a slower response to escitalopram treatment than those without executive functioning complaints. Self-report of executive functioning difficulties may be a useful prognostic indicator for subsequent speed of response to antidepressant medication. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Relative benefit-risk comparing diclofenac to other traditional non-steroidal anti-inflammatory drugs and cyclooxygenase-2 inhibitors in patients with osteoarthritis or rheumatoid arthritis: a network meta-analysis.

PubMed

van Walsem, Anneloes; Pandhi, Shaloo; Nixon, Richard M; Guyot, Patricia; Karabis, Andreas; Moore, R Andrew

2015-03-19

There is argument over the benefits and risks of drugs for treating chronic musculoskeletal pain. This study compared the efficacy, safety, and tolerability of diclofenac, ibuprofen, naproxen, celecoxib, and etoricoxib for patients with pain caused by osteoarthritis (OA) or rheumatoid arthritis (RA). A systematic literature review used Medline and EMBASE to identify randomised controlled trials. Efficacy outcomes assessed included: pain relief measured by visual analogue scale (VAS); Western Ontario McMaster Universities Arthritis Index (WOMAC) VAS or WOMAC Likert scale; physical functioning measured by WOMAC VAS or Likert scale; and patient global assessment (PGA) of disease severity measured on VAS or 5-point Likert scale. Safety outcomes included: Antiplatelet Trialists' Collaboration (APTC), major cardiovascular (CV) and major upper gastrointestinal (GI) events, and withdrawals. Data for each outcome were synthesized by a Bayesian network meta-analysis (NMA). For efficacy assessments, labelled doses for OA treatment were used for the base case while labelled doses for RA treatment were also included in the sensitivity analysis. Pooled data across dose ranges were used for safety. Efficacy, safety, and tolerability data were found for 146,524 patients in 176 studies included in the NMA. Diclofenac (150 mg/day) was likely to be more effective in alleviating pain than celecoxib (200 mg/day), naproxen (1000 mg/day), and ibuprofen (2400 mg/day), and similar to etoricoxib (60 mg/day); a lower dose of diclofenac (100 mg/day) was comparable to all other treatments in alleviating pain. Improved physical function with diclofenac (100 and 150 mg/day) was mostly comparable to all other treatments. PGA with diclofenac (100 and 150 mg/day) was likely to be more effective or comparable to all other treatments. All active treatments were similar for APTC and major CV events. Major upper GI events with diclofenac were lower compared to naproxen and ibuprofen, comparable to celecoxib, and higher than etoricoxib. Risk of withdrawal with diclofenac was lower compared to ibuprofen, similar to celecoxib and naproxen, and higher than etoricoxib. The benefit-risk profile of diclofenac was comparable to other treatments used for pain relief in OA and RA; benefits and risks vary in individuals and need consideration when making treatment decisions.

Interactions of atenolol with alprazolam/escitalopram on anxiety, depression and oxidative stress.

PubMed

Shahzad, Naiyer; Ahmad, Javed; Khan, Wajahatullah; Al-Ghamdi, Saeed S; Ain, M Ruhal; Ibrahim, Ibrahim Abdel Aziz; Akhtar, Mohd; Khanam, Razia

2014-02-01

Anxiety and depression are highly comorbid disorders possibly sharing a common neurobiological mechanism. The dysfunction of serotoninergic, noradrenergic and dopaminergic neurotransmission, abnormal regulation in the hypothalamic-pituitary-adrenal axis (HPA), disturbance of cellular plasticity including reduced neurogenesis, or chronic inflammation connected with high oxidative damage play a crucial role in the development of anxiety and depression. The present study was aimed to investigate the effects of atenolol alone and in combination with alprazolam/escitalopram on anxiety, depression and oxidative stress. Wistar albino rats were subjected to 21 day treatment of drugs then exposed to elevated-plus maze (EPM) and modified forced swim test (MFST), and oxidative stress markers were estimated in isolated brain tissue of all groups. The results indicated that atenolol in combination with alprazolam/escitalopram exhibited antidepressant effects by significantly decreasing the immobility and increasing the swimming behavior in the MFST and anti-anxiety effects by increasing the percentage preference and number of open arm entries as well as time spent in open arm in EPM. Pretreatment with atenolol alone and combination with alprazolam/escitalopram also ameliorated tissue glutathione (GSH) and decreased malondialdehyde (MDA) level significantly which explore antioxidant properties of drugs, and combination augments the therapeutic response of monotherapy in depression. In conclusion behavioral and biological findings indicate that the combination of atenolol with alprazolam/escitalopram has the potential of being highly efficacious in treating anxiety and depressive disorders as well as oxidative stress. Copyright © 2013 Elsevier Inc. All rights reserved.

Quantification of citalopram or escitalopram and their demethylated metabolites in neonatal hair samples by liquid chromatography-tandem mass spectrometry.

PubMed

Frison, Giampietro; Favretto, Donata; Vogliardi, Susanna; Terranova, Claudio; Ferrara, Santo Davide

2008-08-01

Citalopram and escitalopram are highly selective serotonin reuptake inhibitors widely used in the treatment of depression. They exhibit adverse drug reactions and side effects, however, and the development of specific methods for their determination is of great interest in clinical and forensic toxicology. A liquid chromatography-tandem mass spectrometry method has been developed and validated for the assay of citalopram, escitalopram, and their demethylated metabolites in 10-mg hair samples. The analytes were extracted by incubation in methanol and liquid/liquid extraction with diethyl ether/dichloromethane. Gradient elution on a narrow bore C18 column was realized using clomipramine-d3 as an internal standard. Positive ion electrospray ionization and tandem mass spectrometry determination by collision-induced dissociation were performed in an ion trap mass spectrometer. The method exhibited a linear range of 25 to 2000 pg/mg, a quantification limit of 25 pg/mg for all analytes, relative standard deviations in the range of 12.10 to 9.80 (intraassay), and 13.80 to 11.78 (interassay), and accuracies (as percent recovery of the spiked standards) in the range of 90% to 110%; it was applied to the determination of citalopram and escitalopram and their metabolites in hair samples of two newborns to document their in utero exposure to the drugs. The method proved suitable for neonatal hair analysis of citalopram or escitalopram and was applied to two real cases of gestational exposure.

Impact of escitalopram on vagally mediated cardiovascular function in healthy participants: implications for understanding differential age-related, treatment emergent effects.

PubMed

Kemp, Andrew H; Outhred, Tim; Saunders, Sasha; Brunoni, Andre R; Nathan, Pradeep J; Malhi, Gin S

2014-06-01

Black box warnings for young adults under the age of 25 years indicate that antidepressants may increase risk of suicide. While underlying mechanisms for age-related treatment effects remain unclear, vagally mediated cardiovascular function may play a key role. Decreased heart rate (HR) and an increase in its variability (HRV) improve one's capacity to adapt to environmental stress and attenuate risk for suicide. Using a double blind, randomized, placebo-controlled, crossover, experimental study, we examine whether a single dose of escitalopram (20 mg) attenuates cardiovascular responses to stress under experimental conditions and determine whether age moderates these effects. Forty-four healthy females received a single dose of escitalopram (20 mg) and placebo treatment separated by a 1-week interval (>5 half-lives). HR and high frequency HRV (HF HRV normalized units; 0.15-0.40 Hz) were measured during resting state and stress. While escitalopram attenuated the increase in HR and increased HF HRV, these moderate to large effects were only significant in participants over 25 years of age. No beneficial cardiovascular effects of escitalopram were observed in those under the age of 25. Maturational differences in the development of the prefrontal cortex--a critical region in the central network of autonomic control--may underpin these differential findings. This study provides a theoretical framework on which future research on treatment-emergent suicidality in clinical populations could be based.

Effectiveness and Cost-Effectiveness of Antidepressants in Primary Care: A Multiple Treatment Comparison Meta-Analysis and Cost-Effectiveness Model

PubMed Central

Ramsberg, Joakim; Asseburg, Christian; Henriksson, Martin

2012-01-01

Objective To determine effectiveness and cost-effectiveness over a one-year time horizon of pharmacological first line treatment in primary care for patients with moderate to severe depression. Design A multiple treatment comparison meta-analysis was employed to determine the relative efficacy in terms of remission of 10 antidepressants (citalopram, duloxetine escitalopram, fluoxetine, fluvoxamine mirtazapine, paroxetine, reboxetine, sertraline and venlafaxine). The estimated remission rates were then applied in a decision-analytic model in order to estimate costs and quality of life with different treatments at one year. Data Sources Meta-analyses of remission rates from randomised controlled trials, and cost and quality-of-life data from published sources. Results The most favourable pharmacological treatment in terms of remission was escitalopram with an 8- to 12-week probability of remission of 0.47. Despite a high acquisition cost, this clinical effectiveness translated into escitalopram being both more effective and having a lower total cost than all other comparators from a societal perspective. From a healthcare perspective, the cost per QALY of escitalopram was €3732 compared with venlafaxine. Conclusion Of the investigated antidepressants, escitalopram has the highest probability of remission and is the most effective and cost-effective pharmacological treatment in a primary care setting, when evaluated over a one year time-horizon. Small differences in remission rates may be important when assessing costs and cost-effectiveness of antidepressants. PMID:22876296

Effects of escitalopram on symptoms and quality of life in patients with allergic rhinitis.

PubMed

Erkul, Evren; Cingi, Cemal; Özçelik Korkmaz, Müge; Çekiç, Tuğba; Çukurova, Ibrahim; Yaz, Aytekin; Erdoğmuş, Nagehan; Bal, Cengiz

2012-01-01

Insufficient response to treatment and declining quality of life illustrate the continuing need to find new treatment modalities for allergic rhinitis (AR). The purpose of this study was to assess how escitalopram affects symptoms and quality of life among AR patients. This study included 120 patients with AR, who were divided into four treatment groups of 30 patients each. Patients were assessed before treatment and at the end of the 3rd month based on nasal symptom scores, otorhinolaryngological examination, the Rhinoconjunctivitis Quality of Life Questionnaire, and the Beck Depression and Anxiety Inventory. All patients received standardized treatments. Group A patients with positive Beck Depression and Anxiety Inventory scores received escitalopram, and group B patients with positive Beck Depression and Anxiety Inventory scores received placebo. Group C patients with negative Beck Depression and Anxiety Inventory scores received escitalopram, and group D patients with negative Beck Depression and Anxiety Inventory scores received placebo. Anxiety scores pre- and posttreatment revealed a statistically significant reduction in groups A, C, and D. All four groups exhibited reduced posttreatment scores for sleep, nonnasal and noneye symptoms, eye symptoms, and emotions. A statistically significant difference appeared between groups A and B in terms of general complaints and nasal symptom scores. The positive effects of escitalopram on posttreatment quality of life in the Beck-positive patient group were a predictable outcome. Otolaryngologists should pay more attention to the moods of their patients with AR while they evaluate treatment during clinical follow-up visits.

Effect of Escitalopram on Hot Flash Interference: A Randomized, Controlled Trial

PubMed Central

Carpenter, Janet S.; Guthrie, Katherine A.; Larson, Joseph C.; Freeman, Ellen W.; Joffe, Hadine; Reed, Susan D.; Ensrud, Kristine E.; LaCroix, Andrea Z.

2012-01-01

Objectives To estimate the effect of escitalopram 10–20 mg/day versus placebo for reducing hot flash interference in daily life and understand correlates and predictors of reductions in hot flash interference, a key measure of quality of life. Design Multi-site, randomized, double-blind, placebo-controlled clinical trial. Patients 205 midlife women (46% African-American) who met criteria participated. Setting MsFLASH clinical sites in Boston, Indianapolis, Oakland, and Philadelphia. Intervention After baseline, women were randomized to 1 pill of escitalopram 10 mg/day (n=104) or placebo (n=101) with follow-up at 4- and 8-weeks. At week 4, those not achieving 50% fewer hot flashes were increased to 2 pills daily (20 mg/day or 2 placebo pills). Main outcome measures The Hot Flash Related Daily Interference Scale; Correlates were variables from hot flash diaries; Predictors were baseline demographics, clinical variables, depression, anxiety, sleep quality, and hot flashes. Results Compared to placebo, escitalopram significantly reduced hot flash interference by 6.0 points at week 4 and 3.4 points at week 8 more than placebo (p=0.012). Reductions in hot flash interference correlated with changes in hot flash diary variables. However, baseline variables did not significantly predict reductions in hot flash interference. Conclusions Escitalopram 10–20mg/day for 8 weeks improves women’s quality of life and this benefit did not vary by demographic, clinical, mood, sleep, or hot flash variables. PMID:22480818

Pre-treatment factor structures of the Montgomery and Åsberg Depression Rating scale as predictors of response to escitalopram in Indian patients with non-psychotic major depressive disorder.

PubMed

Basu, Aniruddha; Chadda, Rakesh; Sood, Mamta; Rizwan, S A

2017-08-01

Major Depressive Disorder (MDD) is a broad heterogeneous construct resolving into several symptom-clusters by factor analysis. The aim was to find the factor structures of MDD as per Montgomery and Asberg Depression Rating Scale (MADRS) and whether they predict escitalopram response. In a longitudinal study at a tertiary institute in north India, 116 adult out-patients with non-psychotic unipolar MDD were assessed with MADRS before and after treatment with escitalopram (10-20mg) over 6-8 weeks for drug response. For total 116 patients pre-treatment four factor structures of MADRS extracted by principal component analysis with varimax rotation altogether explained a variance of 57%: first factor 'detachment' (concentration difficulty, lassitude, inability to feel); second factor 'psychic anxiety' (suicidal thoughts and inner tension); third 'mood-pessimism' (apparent sadness, reported sadness, pessimistic thoughts) and fourth 'vegetative' (decreased sleep, appetite). Eighty patients (68.9%) who completed the study had mean age 35.37±10.9 yrs, majority were male (57.5%), with mean pre-treatment MADRS score 28.77±5.18 and majority (65%) having moderate severity (MADRS <30). Among them 56 (70%) responded to escitalopram. At the end of the treatment there were significant changes in all the 4 factor structures (p<0.01). Vegetative function was an important predictor of response (p<0.01, odd's ratio: 1.3 [1.1-1.6] 95% CI). Melancholia significantly predicted non-response (p=0.04). Non-psychotic unipolar major depression having moderate severity in north Indian patients as per MADRS resolved into four factor-structures all significantly improved with adequate escitalopram treatment. Understanding the factor structure is important as they can be important predictor of escitalopram response. Copyright © 2017 Elsevier B.V. All rights reserved.

Combined Effects of Acamprosate and Escitalopram on Ethanol Consumption in Mice

PubMed Central

Ho, Ada Man-Choi; Qiu, Yanyan; Jia, Yun-Fang; Aguiar, Felipe S.; Hinton, David J.; Karpyak, Victor M.; Weinshilboum, Richard M.; Choi, Doo-Sup

2016-01-01

Background Major depression is one of the most prevalent psychiatry comorbidities of alcohol use disorders (AUD). Since negative emotions can trigger craving and increase the risk of relapse, treatments that target both conditions simultaneously may augment treatment success. Previous studies showed a potential synergist effect of FDA approved medication for AUD acamprosate and the antidepressant escitalopram. In this study, we investigated the effects of combining acamprosate and escitalopram on ethanol consumption in stress-induced depressed mice. Methods Forty singly-housed C57BL/6J male mice were subjected to chronic unpredictable stress. In parallel, 40 group-housed male mice were subjected to normal husbandry. After 3 weeks, depressive- and anxiety-like behaviors and ethanol consumption were assessed. For the next 7 days, mice were injected with saline, acamprosate (200 mg/kg; twice/day), escitalopram (5 mg/kg; twice/day), or their combination (n = 9–11/drug group/stress group). Two-bottle choice limited access drinking of 15% ethanol and tap water was performed 3 hours into dark phase for 2 hours immediately after the dark phase daily injection. Ethanol drinking was monitored for another 7 days without drug administration. Results Mice subjected to the chronic unpredictable stress paradigm for 3 weeks showed apparent depression- and anxiety-like behaviors compared to their non-stressed counterparts including longer immobility time in the forced swim test and lower sucrose preference. Stressed mice also displayed higher ethanol consumption and preference in a 2-bottle choice drinking test. During the drug administration period, the escitalopram-only and combined drug groups showed significant reduction in ethanol consumption in non-stressed mice, while only the combined drug group showed significantly reduced consumption in stressed mice. However, such reduction did not persist into the post-drug administration period. Conclusions The combination of acamprosate and escitalopram suppressed ethanol intake in both non-stressed and stressed mice, hence this combination is potentially helpful for AUD individuals with or without comorbid depression to reduce alcohol use. PMID:27184383

Ziprasidone Augmentation of Escitalopram for Major Depressive Disorder: Cardiac, Endocrine, Metabolic, and Motoric Effects in a Randomized, Double-Blind, Placebo-Controlled Study.

PubMed

Mischoulon, David; Shelton, Richard C; Baer, Lee; Bobo, William V; Curren, Laura; Fava, Maurizio; Papakostas, George I

2017-04-01

To examine motoric, cardiovascular, endocrine, and metabolic effects of adjunctive ziprasidone in adults with major depressive disorder (MDD) and prior nonresponse to 8 weeks of open-label escitalopram. A multicenter, parallel, randomized, double-blind, placebo-controlled trial was conducted at 3 US academic medical centers from July 2008 to October 2013. Recruited were 139 outpatients with persistent DSM-IV MDD following an 8-week open-label trial of escitalopram. Subjects were then randomized to adjunctive ziprasidone (escitalopram + ziprasidone, n = 71) or placebo (escitalopram + placebo, n = 68) for 8 additional weeks. Cardiac and metabolic measures were obtained at each treatment visit. Barnes Akathisia Scale and Abnormal Involuntary Movement Scale (AIMS) scores were also obtained. Changes in outcome measures for each treatment group were compared by independent-samples t test. A trend toward significance (P = .06) in corrected QT interval (QTc) increase was observed for ziprasidone (mean [SD] = 8.8 [20.2] milliseconds) versus placebo (-0.02 [25.5] milliseconds). Ziprasidone-treated patients had a significantly greater increase in global akathisia scores (P = .01) and significant weight increase (mean [SD] = 3.5 [11.8] kg, or 7.7 [26.1] lb) compared to placebo (1.0 [6.4] kg, or 2.2 [14.1] lb) (P = .03). No significant changes in AIMS scores were observed for either treatment group. Adjunctive ziprasidone, added to escitalopram, led to a greater weight gain and greater but modest akathisia compared to placebo. The effect of ziprasidone on QTc showed a trend toward significance, and therefore caution should be used in the administration of ziprasidone. While ziprasidone augmentation in patients with MDD appears safe, precautions should be taken in practice, specifically regular monitoring of electrocardiogram, weight, extrapyramidal symptoms, and involuntary movements. ClinicalTrials.gov identifier: NCT00633399​​. © Copyright 2016 Physicians Postgraduate Press, Inc.

Is Escitalopram Really Relevantly Superior to Citalopram in Treatment of Major Depressive Disorder? A Meta-analysis of Head-to-head Randomized Trials

PubMed Central

Trkulja, Vladimir

2010-01-01

Aim To evaluate clinical relevance of differences between escitalopram and citalopram (equimolar) for major depressive disorder. Methods Review and meta-analysis of comparative randomized controlled trials (RCT). Comparisons were in relation to Montgomery-Asberg depression rating scale (MADRS) score reduction at weeks 1 (5 RCTs), 4 (5 RCTs), 6 (4 RCTs), 8 (5 RCTs), and 24 (1 RCT); proportion of responders at weeks 2, 4, 6 (2 RCTs for each time point), 8 (5 RCTs), and 24 (1 RCT); clinical global impression-severity (CGI-S) reduction at weeks 6 (1 RCT), 8 (5 RCTs), and 24 (1 RCT), and discontinuation due to adverse events or inefficacy during short-term (up to 8 weeks) and medium-term (24 weeks) treatment. Results MADRS reduction was greater with escitalopram, but 95% confidence intervals (CI) around the mean difference were entirely or largely below 2 scale points (minimally important difference) and CI around the effect size (ES) was below 0.32 (“small”) at all time points. Risk of response was higher with escitalopram at week 8 (relative risk, 1.14; 95% CI, 1.04 to 1.26) but number needed to treat was 14 (95% CI, 7 to 111). All 95% CIs around the mean difference and ES of CGI-S reduction at week 8 were below 0.32 points and the limit of “small,” respectively. Data for severe patients (MADRS≥30) are scarce (only 1 RCT), indicating somewhat greater efficacy (response rate and MADRS reduction at week 8, but not CGI-S reduction) of escitalopram, but without compelling evidence of clinically relevant differences. Discontinuations due to adverse events or inefficacy up to 8 weeks of treatment were comparable. Data for the period up to 24 weeks are scarce and inconclusive. Conclusion Presently, the claims about clinically relevant superiority of escitalopram over citalopram in short-to-medium term treatment of major depressive disorder are not supported by evidence. PMID:20162747

Is escitalopram really relevantly superior to citalopram in treatment of major depressive disorder? A meta-analysis of head-to-head randomized trials.

PubMed

Trkulja, Vladimir

2010-02-01

To evaluate clinical relevance of differences between escitalopram and citalopram (equimolar) for major depressive disorder. Review and meta-analysis of comparative randomized controlled trials (RCT). Comparisons were in relation to Montgomery-Asberg depression rating scale (MADRS) score reduction at weeks 1 (5 RCTs), 4 (5 RCTs), 6 (4 RCTs), 8 (5 RCTs), and 24 (1 RCT); proportion of responders at weeks 2, 4, 6 (2 RCTs for each time point), 8 (5 RCTs), and 24 (1 RCT); clinical global impression-severity (CGI-S) reduction at weeks 6 (1 RCT), 8 (5 RCTs), and 24 (1 RCT), and discontinuation due to adverse events or inefficacy during short-term (up to 8 weeks) and medium-term (24 weeks) treatment. MADRS reduction was greater with escitalopram, but 95% confidence intervals (CI) around the mean difference were entirely or largely below 2 scale points (minimally important difference) and CI around the effect size (ES) was below 0.32 ("small") at all time points. Risk of response was higher with escitalopram at week 8 (relative risk, 1.14; 95% CI, 1.04 to 1.26) but number needed to treat was 14 (95% CI, 7 to 111). All 95% CIs around the mean difference and ES of CGI-S reduction at week 8 were below 0.32 points and the limit of "small," respectively. Data for severe patients (MADRS> or =30) are scarce (only 1 RCT), indicating somewhat greater efficacy (response rate and MADRS reduction at week 8, but not CGI-S reduction) of escitalopram, but without compelling evidence of clinically relevant differences. Discontinuations due to adverse events or inefficacy up to 8 weeks of treatment were comparable. Data for the period up to 24 weeks are scarce and inconclusive. Presently, the claims about clinically relevant superiority of escitalopram over citalopram in short-to-medium term treatment of major depressive disorder are not supported by evidence.

Can we well assess the relative efficacy and tolerability of a new drug versus others at the time of marketing authorization using mixed treatment comparisons? A detailed illustration with escitalopram

PubMed Central

Llorca, Pierre-Michel; Lançon, Christophe; Brignone, Mélanie; Painchault, Caroline; Rive, Benoit; Toumi, Mondher; François, Clément

2015-01-01

Objective To assess the variation of relative efficacy and tolerability of an antidepressant versus others based on both pre-marketing (registration studies) and post-marketing studies versus pre-marketing studies only in patients with major depressive disorder. Methods The relative efficacy and tolerability of antidepressants was assessed by mixed treatment comparisons (MTCs) using data acquired over two time periods: before registration of the reference drug escitalopram (1989–2002) and up to 5 years later (1989–2007). Ranking probability outputs were presented for efficacy, using change from baseline to 8 weeks on Montgomery–Åsberg Depression Rating Scale total score, and tolerability, using withdrawals due to adverse events. Results The relative efficacy and tolerability of some selected antidepressants, including escitalopram, varied considerably over the two time periods. The improved relative efficacy and tolerability of escitalopram over time, compared with citalopram, was demonstrated by greater separation of ranking probability curves for efficacy and tolerability. In 2002, escitalopram ranked low with 13.9% and 5.1% probability of being in the top four antidepressants’ relative efficacy and tolerability, respectively. In 2007, ranking probabilities for relative efficacy and tolerability of escitalopram increased to 52.5% and 82.1%, respectively. Conclusions Time of marketing authorization may not be the most appropriate time to evaluate the relative efficacy and tolerability of a new antidepressant based on MTC approach due to the asymmetry of information between new and older compounds. However, the first evaluation of relative effect of a new drug for health technology assessment recommendations is commonly done at this time. Re-evaluation of a drug several years after its launch is likely to provide a more accurate indication of its relative efficacy and tolerability. PMID:27123184

Erythema multiforme major secondary to a cosmetic facial cream: first case report.

PubMed

Farquharson, Andre A; Stoopler, Eric T; Houston, Alicia M; Brown, Ronald S

2016-01-01

Oral erythema multiforme (EM) major is an acute immune-mediated disorder typically involving the oral mucosa, triggered by a hypersensitivity reaction to an antigen. A 59-year-old woman presented to an oral medicine clinic with a chief complaint of "mystery disease" of 1 year's duration. The condition was described as repeated episodes of severe, painful, asymmetric oral lesions that responded to systemic steroid therapy. A previous oral biopsy described fibrinoid necrosis, mixed inflammation, and granulation tissue. A regimen of descending-dose prednisone was administered, and 3 weeks later the tissues appeared to be partially healed. Direct immunofluorescence staining of a biopsied oral mucosal lesion was negative. To rule out a drug causation, the patient discontinued hydrochlorothiazide and escitalopram oxalate. However, on steroid tapering, episodic lesions recurred. The patient was placed on combination systemic prednisone and azathioprine. The oral lesions resolved again, but new episodes occurred immediately after tapering. The patient's daily facial cosmetics were evaluated, and she was asked to stop using cosmetics with the active ingredient octocrylene. After eliminating the use of facial cosmetics containing octocrylene, the episodes no longer recurred. We report a case of cosmetic-induced EM major and suggest that the triggering allergen is octocrylene. Copyright © 2016 Elsevier Inc. All rights reserved.

CYP2C19 variation, not citalopram dose nor serum level, is associated with QTc prolongation.

PubMed

Kumar, Yingying; Kung, Simon; Shinozaki, Gen

2014-12-01

Recently, a FDA Safety Communication warned of a dose-dependent risk for QTc prolongation with citalopram, which is metabolized by CYP2C19 of the cytochrome P450 system. We investigate associations between citalopram and escitalopram dose, serum concentration, CYP2C19 phenotype, and QTc. We undertook a retrospective chart review of citalopram or escitalopram patients with the inclusion criteria of consistent medication dose, CYP2C19 phenotype (extensive metabolizers [EM], intermediate metabolizers [IM], poor metabolizers [PM]), and QTc interval on ECG. We further identified 42 citalopram users with citalopram serum concentration measurements and ECG. Regression and one-way ANOVA were used to examine the relationship between citalopram dose, citalopram serum concentration, CYP2C19 phenotype, and QTc interval. Of 75 citalopram patients, the EM group had significantly shorter QTc intervals than a combined IM+PM group (427.1±23.6 ms vs. 440.1±26.6 ms, one-tailed t-test, p=0.029). In the 80 escitalopram cohort, there was no significant difference in QTc between phenotype groups. There was no statistical correlation between citalopram (p=0.62) or escitalopram (p=0.30) dose and QTc. QTc was not associated with citalopram serum level (p=0.45). In contrast to the FDA warning, this study found no association between citalopram/escitalopram dose and QTc. However, PM of the drug tended to have longer QTc intervals. Our findings suggest cytochrome P450 genotyping in select patients may be helpful to guide medication optimization while limiting harmful effects. © The Author(s) 2014.

Escitalopram: superior to citalopram or a chiral chimera?

PubMed

Svensson, Staffan; Mansfield, Peter R

2004-01-01

Escitalopram is the active isomer of the antidepressant citalopram. In theory single-isomer drugs may be superior but few have been found to have clinically significant advantages. The manufacturer claims that escitalopram has more efficacy and a faster onset of effect than citalopram. The purpose of this study was to assess how far these claims are justified. Relevant trial reports were requested from H. Lundbeck A/S and the Swedish drug regulatory authority. The trials consisted of a pooled analysis of 1,321 patients from one unpublished, one partly published and one published eight-week trial, as well as a 24-week trial with 357 patients published as a poster. The studies compared escitalopram with placebo and/or citalopram in outpatients aged or=18 years who met specified criteria for depression. The trials' quality was assessed with Moncrieff et al.'s quality assessment instrument and the results compared with the claims from the advertisements. The advertising claims are not justified because they are based on secondary outcomes, non-intention-to-treat analyses and arbitrarily defined subgroups. The subgroup results are inconsistent. Methodological flaws in the trials could account for the differences found. Even if the differences claimed were real they appear too small to justify higher prices. On the evidence available to us the manufacturer's claims of superiority for escitalopram over citalopram are unwarranted. The Swedish and Danish drug regulatory authorities reached similar conclusions. This highlights the need for wider dissemination of national authorities' statements to other countries affected by the European Union's mutual recognition procedure. Copyright 2004 S. Karger AG, Basel

Rheology-A pre-formulation tool for evaluating mechanical and thermal properties of transdermal formulations

NASA Astrophysics Data System (ADS)

Modi, Nisarg

Rheological characterization of pharmaceutical gel is of importance as it provides fundamental information required for the assessment of some of the final properties of a product such as viscosity, elasticity, quality and physical storage stability. The effect of formulation and process variables on product characteristics such as consistency, drug release, and physical stability can also be attained. Moreover, some of the transdermal patch problems such as leaking from reservoir patch or cold flow in matrix patch can also be estimated using rheological characterization. During this research, various tests were employed to characterize the mechanical properties of gel such as oscillation test (Frequency and Amplitude Sweep), flow and viscosity curves and yield point measurements, as well as temperature sweep and temperature ramp test. The present studies evaluate rheological properties of hydroxypropyl cellulose (Klucel HF) gels prepared containing fatty acids with different carbon chain length at different homogenization speed. A controlled stress rheometer was used to study the effect of different number of carbon chain fatty acids, homogenization speed and storage period on the rheological properties and microstructure of transdermal gels. The studies demonstrated that as the carbon chain length increased (C10-C 18) the thixotropic area decreased, which suggested that the stability of gel structure was increased with increase in carbon chain of fatty acids. Cohesive Energy was affected by the homogenization speed and carbon chain of fatty acids. There was decreased in cohesive energy as increase in carbon chain of fatty acids. Temperature sweep data revealed that gels prepared with oleic acid (C18) at 25000 RPM gave the best thermal stability after the longest storage period (60-Days) compare to the capric(C10) acid and Lauirc (C12) acid. There was only 31% decreased in temperature loop area for oleic (C18) acid as compare to 54% and 86% for capric (C10) acid and lauric acid (C12) respectively. During different mixing speeds at initial time period (t=0), oleic acid showed lowest temperature loop area, which was not affected by storage period. Furthermore, by applying power law model to frequency sweep data, mechanical propereties of transdermal gels were evaluated. Transdermal gels are "physical gels" in nature which showed both frequency dependency and also had a cross-over point. Moreover, the value of n is less than 1. Time Temperature superposition principle can apply to the rheological data of Transdermal gels to obtain the thermal properties of formulations. Thermal properties of transdermal gels are very difficult to measure using traditional DSC equipment. By applying TTS principle, frequency sweep data were obtained between 5-50 °C and extrapolated to achieve the glass transition temperature, free volume and thermal expansion co-efficient of the formulations. Last but not least, In-vitro studies using human cadaver skin showed that Capric acid is the best permeability enhancing agent for escitalopram oxalate in current formulations. Furthermore, increase in carbon chain length of fatty acids decreased the permeability enhancing effect of Escitalopram Oxalate through human cadaver skin during In-vitro diffusion studies.

[Safety and efficacy of oral escitalopram as continuation treatment of intravenous citalopram, in patients with major depressive disorder--the navigade switch study].

PubMed

Schmitt, L; Arbus, C; Tonnoir, B

2006-01-01

Intravenous (iv) administration of an antidepressant is a common practice in some European countries, particularly in France, Spain, and Italy in the initial treatment phase of hospitalised, severe depressed patients. After a beneficial response is observed, patients are switched to an oral formulation. The approved treatment period of the iv form of citalopram is limited to 8-10 days. The high bioavailability of citalopram permits the use of identical iv and oral doses. Citalopram is a racemate, consisting of a 1:1 mixture of the S- and R-enantiomers. The therapeutically active component is the S-enantiomer (escitalopram). Pharmacokinetic single dose administration studies in healthy subjects have demonstrated that daily oral administration of 20 mg of escitalopram or 40 mg citalopram results in similar plasma concentrations of the S-enantiomer of citalopram. This open-label multicentre French prospective study investigated the tolerability and efficacy of oral escitalopram 10 and 20 mg/day, administered for a 6-week period as continuation treatment of citalopram (20 mg or 40 mg daily) intravenous (iv), in patients with Major Depressive Disorder. A total of 171 patients were enrolled, of whom 147 (85%) completed the study. The mean MADRS score at inclusion (last citalopram dose) was 31.6 +/- 9.9. The total MADRS score decreased after 3 days of oral treatment with escitalopram. Escitalopram demonstrated a continuous effect in treating depressive symptoms throughout the study. The decrease in MADRS mean total score from baseline was statistically significant to each visit (day 3, 15; p < 0.0001). At final visit (J42), the decrease was - 18.9 +/- 11.7 (p < 0.0001) and the MADRS mean total score was 12.7 +/- 9.3. There were no differences seen in the patient response comparing gender, age, and the single or recurrent episodes. The changes of Clinical Global Impression scores (CGI-S, CGI-I, PGE-Patient Global Evaluation) were also indicative of an improvement of the patients' depression. The CGI-I and PGE scores were significantly correlated indicating good agreement between investigator and patient in rating the degree of improvement. At the end of the study, 67% of patients were classified as responders (decrease of MADRS score from baseline > or = 50%), and the majority of them were considered remitters (final MADRS score < or = 12). Overall, the switch from intravenous citalopram to oral escitalopram was well tolerated in the study population. In all, 57 patients (33%) reported at least one adverse event (AE) during the study (21 patients in the 10 mg group and 36 patients in the 20 mg group); of these, 7 patients (4%) withdrew from the study. The most frequently reported AEs were suggestive of residual symptoms of depression (anxiety, 9%; insomnia, 5% of patients). In conclusion, in this study oral escitalopram (10 mg or 20 mg) was well tolerated as continuation treatment after switching from intravenous citalopram (20 mg or 40 mg). From the efficacy and safety data of this study, it can be concluded that the switch from citalopram iv to oral escitalopram (10 and 20 mg/day) is effective in decreasing depressive symptoms, and could be safely proposed in patients with major depressive disorder.

Escitalopram treatment of pathological gambling with co-occurring anxiety: an open-label pilot study with double-blind discontinuation.

PubMed

Grant, Jon E; Potenza, Marc N

2006-07-01

Although co-occurring disorders are common in pathological gambling (PG), investigations of the response to pharmacotherapy in individuals with PG and co-occurring psychiatric symptomatology are limited. Thirteen subjects with DSM-IV PG and co-occurring anxiety were treated in a 12-week open-label trial of escitalopram. Subjects were assessed with the Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling (PG-YBOCS; primary outcome measure), the Hamilton Anxiety Rating Scale (HAM-A), the Clinical Global Impressions scale (CGI), and measures of psychosocial functioning and quality of life. Those subjects who 'responded' (defined as a 30% or greater reduction in PG-YBOCS total score at endpoint) were offered inclusion in an 8-week double-blind discontinuation phase. PG-YBOCS scores decreased from a mean of 22.2+/-4.5 at baseline to 11.9+/-10.7 at endpoint (P=0.002) and 61.5% were responders. Scores on the HAM-A decreased by 82.8% over the 12-week period (mean of 15.9+/-3.2 at baseline to a mean of 2.8+/-3.6 at endpoint) (P<0.001). On the CGI, 38.5% of subjects (n=5) were 'very much improved' and 23.1% (n=3) were 'much improved' by study endpoint. The Sheehan Disability Scale, Perceive Stress Scale and Quality of Life Inventory all showed improvement (P< or = 0.001, P=0.002 and P=0.029, respectively). The mean end-of-study dose of escitalopram was 25.4+/-6.6 mg/day. Of three subjects assigned to escitalopram during the discontinuation phase, none reported statistically significant worsening of gambling symptoms. However, one subject assigned to placebo reported that gambling symptoms returned within 4 weeks. Open-label escitalopram treatment was associated with improvements in gambling and anxiety symptoms and measures of psychosocial functioning and quality of life. Larger, longer, placebo-controlled, double-blind studies are needed to evaluate further the safety and tolerability of escitalopram in the treatment of PG and co-occurring anxiety.

Effect of Vortioxetine vs. Escitalopram on Sexual Functioning in Adults with Well-Treated Major Depressive Disorder Experiencing SSRI-Induced Sexual Dysfunction.

PubMed

Jacobsen, Paula L; Mahableshwarkar, Atul R; Chen, Yinzhong; Chrones, Lambros; Clayton, Anita H

2015-10-01

Sexual dysfunction is common with serotonergic antidepressants, including selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), and does not resolve in most patients. Vortioxetine, an antidepressant with a multimodal mechanism of action, has shown low rates of sexual dysfunction in previous major depressive disorder (MDD) trials. This study compared the effects of vortioxetine and escitalopram on sexual functioning in adults with well-treated MDD experiencing treatment-emergent sexual dysfunction (TESD). Participants treated with, and responding to, citalopram, paroxetine, or sertraline were randomized to switch to either vortioxetine (10/20 mg; n = 225) or escitalopram (10/20 mg; n = 222) for 8 weeks. Sexual function was assessed using the Changes in Sexual Functioning Questionnaire Short Form (CSFQ-14), and antidepressant efficacy was assessed using the Montgomery-Åsberg Depression Rating Scale (MADRS), Clinical Global Impressions (CGI) scale, and Profile of Mood States brief form (POMS-brief). Safety and tolerability were also assessed. The primary endpoint was change from baseline in the CSFQ-14 total score after 8 weeks of treatment. The MADRS, CGI, and POMS-brief were used to assess antidepressant efficacy. Safety was assessed via adverse events, vital signs, electrocardiograms, laboratory values, weight, and physical examination findings. Vortioxetine showed significantly greater improvements in CSFQ-14 total score (8.8 ± 0.64, mean ± standard error) vs. escitalopram (6.6 ± 0.64; P = 0.013). Benefits vs. escitalopram were significant on four of five dimensions and all three phases of sexual functioning assessed by the CSFQ-14 (P < 0.05). Antidepressant efficacy continued in both groups, with similar, but slight, improvements in MADRS and CGI scores. Vortioxetine and escitalopram had similar clinical efficacy profiles in this study, with safety profiles similar to previous trials. Nausea (n = 9, 4.0%) was the most common treatment-emergent adverse event leading to discontinuation of vortioxetine. Switching antidepressant therapy to vortioxetine may be beneficial for patients experiencing sexual dysfunction during antidepressant therapy with SSRIs. © 2015 International Society for Sexual Medicine.

Combined Effects of Acamprosate and Escitalopram on Ethanol Consumption in Mice.

PubMed

Ho, Ada Man-Choi; Qiu, Yanyan; Jia, Yun-Fang; Aguiar, Felipe S; Hinton, David J; Karpyak, Victor M; Weinshilboum, Richard M; Choi, Doo-Sup

2016-07-01

Major depression is one of the most prevalent psychiatry comorbidities of alcohol use disorders (AUD). As negative emotions can trigger craving and increase the risk of relapse, treatments that target both conditions simultaneously may augment treatment success. Previous studies showed a potential synergistic effect of Food and Drug Administration approved medication for AUD acamprosate and the antidepressant escitalopram. In this study, we investigated the effects of combining acamprosate and escitalopram on ethanol (EtOH) consumption in stress-induced depressed mice. Forty singly housed C57BL/6J male mice were subjected to chronic unpredictable stress. In parallel, 40 group-housed male mice were subjected to normal husbandry. After 3 weeks, depressive- and anxiety-like behaviors and EtOH consumption were assessed. For the next 7 days, mice were injected with saline, acamprosate (200 mg/kg; twice/d), escitalopram (5 mg/kg; twice/d), or their combination (n = 9 to 11/drug group/stress group). Two-bottle choice limited-access drinking of 15% EtOH and tap water was performed 3 hours into dark phase immediately after the daily dark phase injection. EtOH drinking was monitored for another 7 days without drug administration. Mice subjected to the chronic unpredictable stress paradigm for 3 weeks showed apparent depression- and anxiety-like behaviors compared to their nonstressed counterparts including longer immobility time in the forced swim test and lower sucrose preference. Stressed mice also displayed higher EtOH consumption and preference in a 2-bottle choice drinking test. During the drug administration period, the escitalopram-only and combined drug groups showed significant reduction in EtOH consumption in nonstressed mice, while only the combined drug group showed significantly reduced consumption in stressed mice. However, such reduction did not persist into the postdrug administration period. The combination of acamprosate and escitalopram suppressed EtOH intake in both nonstressed and stressed mice; hence, this combination is potentially helpful for AUD individuals with or without comorbid depression to reduce alcohol use. Copyright © 2016 by the Research Society on Alcoholism.

Efficacy of escitalopram monotherapy in the treatment of major depressive disorder

PubMed Central

Li, Guanjun; Shen, Yifeng; Luo, Jianfeng; Li, Huafang

2017-01-01

Abstract This study aimed to evaluate the efficacy of escitalopram monotherapy in the treatment of major depressive disorder (MDD) on the basis of pooled data analysis of 4 Chinese clinical trials. A total of 649 outpatients with MDD score of ≥18 at the 17-item Hamilton Depression Rating Scale (HAMD17) were included across 4 eligible studies. Patients were treated with 10 mg/day escitalopram for 2 weeks, and then 20 mg/day escitalopram was administered if the clinical response was poor. The change in total HAMD17 score was significantly greater in moderate MDD group than in other subgroups (P < .001), but the proportion of responders and remission rate in moderate MDD group were markedly lower than in mild MDD group. As compared to patients with concomitant anxiety, anxiety free patients showed significant improvement in total HAMD17 score at days 14 and 28 (P < .05). However, there was no significant difference in the change of total HAMD17 score at day 7 and the end of study. According to clinical global impression (CGI) score, the total response rate (very much improved and much improved) was 86.7%. There were 479 adverse events (AEs), but serious AEs were not observed. A total of 3.39% (22/649) of patients withdrew from these studies due to AEs. The most common (incidence ≥2.0%) AEs were nausea, dry mouth, somnolence, dizziness, fatigue, dyspepsia, liver dysfunction, and loss of appetite. Escitalopram monotherapy is effective and safe in the treatment of MDD in Chinese patients, and therapeutic efficacy is dependent on the severity of MDD. Further study is needed to identify better predictors of therapeutic responses. PMID:28953649

High-Dose Citalopram and Escitalopram and the Risk of Out-of-Hospital Death.

PubMed

Ray, Wayne A; Chung, Cecilia P; Murray, Katherine T; Hall, Kathi; Stein, C Michael

2017-02-01

Studies demonstrating that higher doses of citalopram (> 40 mg) and escitalopram (> 20 mg) prolong the corrected QT interval prompted regulatory agency warnings, which are controversial, given the absence of confirmatory clinical outcome studies. We compared the risk of potential arrhythmia-related deaths for high doses of these selective serotonin reuptake inhibitors (SSRIs) to that for equivalent doses of fluoxetine, paroxetine, and sertraline. The Tennessee Medicaid retrospective cohort study included 54,220 persons 30-74 years of age without cancer or other life-threatening illness who were prescribed high-dose SSRIs from 1998 through 2011. The mean age was 47 years, and 76% were female. Demographic characteristics and comorbidity for individual SSRIs were comparable. Because arrhythmia-related deaths are typically sudden and occur outside the hospital, we analyzed out-of-hospital sudden unexpected death as well as sudden cardiac deaths, a more specific indicator of proarrhythmic effects. The adjusted risk of sudden unexpected death for citalopram did not differ significantly from that for the other SSRIs. The respective hazard ratios (HRs) for citalopram versus escitalopram, fluoxetine, paroxetine, and sertraline were 0.84 (95% CI, 0.40-1.75), 1.24 (95% CI, 0.75-2.05), 0.75 (95% CI, 0.45-1.24), and 1.53 (95% CI, 0.91-2.55). There were no significant differences for sudden cardiac death or all study deaths, nor were there significant differences among high-risk patients (≥ 60 years of age, upper quartile baseline cardiovascular risk). Escitalopram users had no significantly increased risk for any study end point. We found no evidence that risk of sudden unexpected death, sudden cardiac death, or total mortality for high-dose citalopram and escitalopram differed significantly from that for comparable doses of fluoxetine, paroxetine, and sertraline. © Copyright 2016 Physicians Postgraduate Press, Inc.

Ontogeny of SERT Expression and Antidepressant-like Response to Escitalopram in Wild-Type and SERT Mutant Mice.

PubMed

Mitchell, Nathan C; Gould, Georgianna G; Koek, Wouter; Daws, Lynette C

2016-08-01

Depression is a disabling affective disorder for which the majority of patients are not effectively treated. This problem is exacerbated in children and adolescents for whom only two antidepressants are approved, both of which are selective serotonin reuptake inhibitor (SSRIs). Unfortunately SSRIs are often less effective in juveniles than in adults; however, the mechanism(s) underlying age-dependent responses to SSRIs is unknown. To this end, we compared the antidepressant-like response to the SSRI escitalopram using the tail suspension test and saturation binding of [(3)H]citalopram to the serotonin transporter (SERT), the primary target of SSRIs, in juvenile [postnatal day (P)21], adolescent (P28), and adult (P90) wild-type (SERT+/+) mice. In addition, to model individuals carrying low-expressing SERT variants, we studied mice with reduced SERT expression (SERT+/-) or lacking SERT (SERT-/-). Maximal antidepressant-like effects were less in P21 mice relative to P90 mice. This was especially apparent in SERT+/- mice. However, the potency for escitalopram to produce antidepressant-like effects in SERT+/+ and SERT+/- mice was greater in P21 and P28 mice than in adults. SERT expression increased with age in terminal regions and decreased with age in cell body regions. Binding affinity values did not change as a function of age or genotype. As expected, in SERT-/- mice escitalopram produced no behavioral effects, and there was no specific [(3)H]citalopram binding. These data reveal age- and genotype-dependent shifts in the dose-response for escitalopram to produce antidepressant-like effects, which vary with SERT expression, and may contribute to the limited therapeutic response to SSRIs in juveniles and adolescents. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

High-Dose Citalopram and Escitalopram and the Risk of Out-of-Hospital Death

PubMed Central

Ray, Wayne A.; Chung, Cecilia P.; Murray, Katherine T.; Hall, Kathi; Stein, C. Michael

2018-01-01

Objective Studies demonstrating higher doses of citalopram (>40mg) and escitalopram (>20mg) prolong the QTc interval prompted regulatory agency warnings, which are controversial, given the absence of confirmatory clinical outcome studies. We compared the risk of potential arrhythmia-related deaths for high doses of these SSRIs to that for equivalent doses of fluoxetine, paroxetine, and sertraline. Method The Tennessee Medicaid retrospective cohort study included 54,220 persons 30–74 years of age without cancer or other life-threatening illness prescribed high-dose SSRIs. The mean age was 47 years and 76% were female. Demographic characteristics and comorbidity for individual SSRIs were comparable. Because arrhythmia-related deaths are typically sudden and occur outside the hospital, we analyzed out-of-hospital sudden unexpected death as well as sudden cardiac deaths, a more specific indicator of pro-arrhythmic effects. Results The adjusted risk of sudden unexpected death for citalopram did not differ significantly from that for the other SSRIs. The respective hazard ratios (HRs) for citalopram versus escitalopram, fluoxetine, paroxetine, and sertraline were 0.84 (95% confidence interval [CI], 0.40–1.75), 1.24 (0.75–2.05), 0.75 (0.45–1.24), and 1.53 (0.91–2.55). There were no significant differences for sudden cardiac death or all study deaths, nor were there significant differences among high-risk patients (≥60 years of age, upper quartile baseline cardiovascular risk). Escitalopram users had no significantly increased risk for any study endpoint. Conclusions We found no evidence that risk of sudden unexpected death, sudden cardiac death, or total mortality for high-dose citalopram and escitalopram differed significantly from that for comparable doses of fluoxetine, paroxetine, and sertraline. PMID:27736049

Fluorimetric quantitation of citalopram and escitalopram in plasma: developing an express method to monitor compliance in clinical trials.

PubMed

Serebruany, Victor; Malinin, Alex; Dragan, Vadim; Atar, Dan; van Zyl, Louis; Dragan, Anatoly

2007-01-01

Selective serotonin reuptake inhibitors (SSRIs) in general, and citalopram/escitalopram in particular, are widely used to treat clinical depression. However, SSRI bioavailability and non-compliance represent major issues, especially in the clinical trials setting. In this context, frequent drug-level measurements for compliance monitoring would be a desirable tool to improve clinical outcomes with SSRIs. However, the liquid chromatography techniques available are expensive, requiring excessive sample preparation, and suffer from high complexity. We sought to develop a rapid method for the measurement of citalopram/escitalopram levels in human plasma by fluorimetry. A total of 34 frozen human plasma samples were thawed at room temperature and repeatedly centrifuged in cellulose to remove aggregates, proteins and solids. Fluorescence spectra were measured in the range 270-450 nm with excitation at 240 nm on a FluoroMax 3 spectrofluorimeter. Control samples contained known concentrations of SSRIs. SSRI absorbance spectra were recorded in the range 230-320 nm. The shape of the spectra and the absorbance of citalopram and escitalopram were very similar, with UV maximum absorbance at 239 nm. The maximum extinction coefficient was epsilon239=15,930 M-1 cm-1 for citalopram and epsilon239=13,630 M-1 cm-1 for escitalopram. The fluorescence spectra of SSRIs are unique and are characterized by the presence of two well-defined conjugated spectra with maxima at 300 and 382 nm. Fluorimetry is very suitable for assessment of plasma SSRI levels. This inexpensive and efficient technique can objectively and reliably quantify drug levels in biological fluids, thereby directly determining the level of patient adherence to the prescribed drug regimen. This method will be useful in a broad spectrum of applications, from compliance/bioavailability assessments in animal and human experiments to utilization in large-scale clinical trials.

[Citalopram, escitalopram and prolonged QT: warning or alarm?].

PubMed

Alvarez, Enric; Vieira, Sara; Garcia-Moll, Xavier

2014-01-01

The alerts issued by regulatory agencies on the potential cardiac toxicity of citalopram and escitalopram have caused alarm among clinicians. A review of the data concerning this topic shows that the alarm should be limited to patients with a history of syncope or poisoning. As a precautionary measure, an electrocardiogram should be performed on elderly patients. Copyright © 2013 SEP y SEPB. Published by Elsevier España. All rights reserved.

Effects of citalopram and escitalopram on fMRI response to affective stimuli in healthy volunteers selected by serotonin transporter genotype.

PubMed

Henry, Michael E; Lauriat, Tara L; Lowen, Steven B; Churchill, Jeffrey H; Hodgkinson, Colin A; Goldman, David; Renshaw, Perry F

2013-09-30

This study was designed to assess whether functional magnetic resonance imaging (fMRI) following antidepressant administration (pharmaco-fMRI) is sufficiently sensitive to detect differences in patterns of activation between enantiomers of the same compound. Healthy adult males (n=11) participated in a randomized, double-blind, cross-over trial with three medication periods during which they received citalopram (racemic mixture), escitalopram (S-citalopram alone), or placebo for 2 weeks. All participants had high expression serotonin transporter genotypes. An fMRI scan that included passive viewing of overt and covert affective faces and affective words was performed after each medication period. Activation in response to overt faces was greater following escitalopram than following citalopram in the right insula, thalamus, and putamen when the faces were compared with a fixation stimulus. For the rapid covert presentation, a greater response was observed in the left middle temporal gyrus in the happy versus fearful contrast following escitalopram than following citalopram. Thus, the combination of genomics and fMRI was successful in discriminating between two very similar drugs. However, the pattern of activation observed suggests that further studies are indicated to understand how to optimally combine the two techniques. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Effects of citalopram and escitalopram on fMRI response to affective stimuli in healthy volunteers selected by serotonin transporter genotype

PubMed Central

Henry, Michael E.; Lauriat, Tara L.; Lowen, Steven B.; Churchill, Jeffrey H.; Hodgkinson, Colin A.; Goldman, David; Renshaw, Perry F.

2015-01-01

This study was designed to assess whether functional magnetic resonance imaging (fMRI) following antidepressant administration (pharmaco-fMRI) is sufficiently sensitive to detect differences in patterns of activation between enantiomers of the same compound. Healthy adult males (n = 11) participated in a randomized, double-blind, cross-over trial with three medication periods during which they received citalopram (racemic mixture), escitalopram (S-citalopram alone), or placebo for 2 weeks. All participants had high expression serotonin transporter genotypes. An fMRI scan that included passive viewing of overt and covert affective faces and affective words was performed after each medication period. Activation in response to overt faces was greater following escitalopram than following citalopram in the right insula, thalamus, and putamen when the faces were compared with a fixation stimulus. For the rapid covert presentation, a greater response was observed in the left middle temporal gyrus in the happy versus fearful contrast following escitalopram than following citalopram. Thus, the combination of genomics and fMRI was successful in discriminating between two very similar drugs. However, the pattern of activation observed suggests that further studies are indicated to understand how to optimally combine the two techniques. PMID:23845563

Gateways to clinical trials.

PubMed

Bayés, M; Rabasseda, X; Prous, J R

2005-12-01

Gateways to Clinical Trials are a guide to the most recent clinical trials in current literature and congresses. The data in the following tables have been retrieved from the Clinical Trials Knowledge Area of Prous Science Integrity, the drug discovery and development portal, http://integrity. prous.com. This issue focuses on the following selection of drugs: 131I-chTNT; Abatacept, adalimumab, alemtuzumab, APC-8015, aprepitant, atazanavir sulfate, atomoxetine hydrochloride, azimilide hydrochloride; Bevacizumab, bortezomib, bosentan, buserelin; Caspofungin acetate, CC-4047, ChAGCD3, ciclesonide, clopidogrel, curcumin, Cypher; Dabigatran etexilate, dapoxetine hydrochloride, darbepoetin alfa, darusentan, denosumab, DMXB-Anabaseine, drospirenone, drospirenone/estradiol, duloxetine hydrochloride, dutasteride; Edodekin alfa, efaproxiral sodium, elaidic acid-cytarabine, erlotinib hydrochloride, ertapenem sodium, escitalopram oxalate, eszopiclone, etonogestrel/testosterone decanoate, exenatide; Fulvestrant; Gefitinib, glycine, GVS-111; Homoharringtonine; ICC-1132, imatinib mesylate, iodine (I131) tositumomab, i.v. gamma-globulin; Levetiracetam, levocetirizine, lintuzumab, liposomal nystatin, lumiracoxib, lurtotecan; Manitimus, mapatumumab, melatonin, micafungin sodium, mycophenolic acid sodium salt; Oblimersen sodium, OGX-011, olmesartan medoxomil, omalizumab, omapatrilat, oral insulin; Parathyroid hormone (human recombinant), pasireotide, peginterferon alfa-2a, peginterferon alfa-2b, peginterferon alfa-2b/ribavirin, phVEGF-A165, pimecrolimus, pitavastatin calcium, plerixafor hydrochloride, posaconazole, pramlintide acetate, prasterone, pregabalin, PT-141; Quercetin; Ranolazine, rosuvastatin calcium, rubitecan, rupatadine fumarate; Sardomozide, sunitinib malate; Tadalafil, talactoferrin alfa, tegaserod maleate, telithromycin, testosterone transdermal patch, TH-9507, tigecycline, tiotropium bromide, tipifarnib, tocilizumab, treprostinil sodium; Valdecoxib, vandetanib, vardenafil hydrochloride hydrate, voriconazole. Copyright 2005 Prous Science. All rights reserved.

Treatment of comorbid anxiety and depression with escitalopram: results of a post-marketing surveillance study.

PubMed

Laux, G; Friede, M; Müller, W E

2013-01-01

In this 16-week post-marketing surveillance (PMS) study, antidepressant effects and tolerability of escitalopram was examined in 2 911 patients with comorbid depression and anxiety. Antidepressant effects were assessed using a modified version of the Montgomery-Åsberg depression rating scale (svMADRS), the Hamilton anxiety scale (HAMA) and the hospital anxiety depression scale (HADS-D) and the clinical global impression scale (CGI-S, CGI-I). Treatment was completed by 2 718 patients, whose severity of depression decreased from a mean svMADRS total score of 33.0 to 8.9. At the end of the study, the remission rate (svMADRS≤12) was 72.9% and the response rate (≥50% decrease in svMADRS score) was 83.1% (LOCF). Similarly, the severity of anxiety symptoms decreased from a mean HAMA total score of 28.8-8.8; the remission rate (HAMA<10) was 63.9% and the response rate (decrease≥50%) was 80.2%. The most frequent adverse events were nausea (1.6%), agitation (1.1%) and fatigue (0.7%). Antidepressant effects and good tolerability of escitalopram were confirmed in everyday practice in patients with comorbid depression and anxiety. The high response and remission rates were within the range reported in previous RTC's of escitalopram vs. comparators or vs. placebo. © Georg Thieme Verlag KG Stuttgart · New York.

Correlates and Escitalopram Treatment Effects on Sleep Disturbance in Patients with Acute Coronary Syndrome: K-DEPACS and EsDEPACS.

PubMed

Kim, Jae-Min; Stewart, Robert; Bae, Kyung-Yeol; Kang, Hee-Ju; Kim, Sung-Wan; Shin, Il-Seon; Hong, Young Joon; Ahn, Youngkeun; Jeong, Myung Ho; Yoon, Jin-Sang

2015-07-01

To investigate the correlates of sleep disturbance and to assess escitalopram treatment effects of depression on sleep disturbance in patients with acute coronary syndrome (ACS). A cross-sectional study in patients with ACS within 2 w post-ACS, and a 24-w double-blind controlled trial of escitalopram against placebo for patients with ACS who have comorbid depressive disorders. A university hospital in South Korea. There were 1,152 patients with ACS who were consecutively recruited. Of 446 patients with comorbid depressive disorders, 300 were randomized to the trial. Sleep disturbance was evaluated by the Leeds Sleep Evaluation Questionnaire. Demographic and clinical characteristics were assessed, including cardiovascular risk factors, current cardiac status, and depressive symptoms. Depressive symptoms were most strongly and consistently associated with sleep disturbance. In addition, older age, female sex, hypertension, and more severe ACS status were associated with certain aspects of sleep disturbance. Escitalopram was significantly superior to placebo for improving sleep disturbance over the 24-w treatment period. These effects were substantially explained by improvement in depressive symptoms. Depression screening is indicated in patients with acute coronary syndrome with sleep disturbance. Successful treatment of depression has beneficial effects on sleep outcomes in these patients. ClinicalTrial.gov identifier for the 24-w drug trial, NCT00419471. © 2015 Associated Professional Sleep Societies, LLC.

Biphasic effects of selective serotonin reuptake inhibitors on anxiety: rapid reversal of escitalopram's anxiogenic effects in the novelty-induced hypophagia test in mice?

PubMed

Koek, Wouter; Mitchell, Nathan C; Daws, Lynette C

2018-06-01

In humans, chronic treatment with selective serotonin reuptake inhibitors (SSRIs) decreases anxiety, unlike acute treatment, which can increase anxiety. Although this biphasic pattern is observed clinically, preclinical demonstrations are rare. In an animal model of antidepressant-induced anxiolytic effects, the novelty-induced hypophagia (NIH) test, a single administration of the SSRI citalopram reportedly elicited anxiogenic-like effects, whereas three administrations over 24 h were sufficient to produce anxiolytic-like effects. Extending these findings, the present study examined the effects of acute and repeated escitalopram in a similar NIH test in a commonly used mouse strain (i.e. C57BL/6J), analyzing results with a method (i.e. survival analysis) that can model the skewed distribution of latencies to consume food and that can deal with censored data (i.e. when consumption does not occur during the test). Saline-treated mice showed robust NIH. Acute escitalopram enhanced NIH, but did so only at a dose (i.e. 32 mg/kg) that similarly enhanced hypophagia in a familiar environment. The effects of escitalopram on NIH did not significantly change after repeated (three times) administration over 24 h. Additional studies are necessary to delineate the conditions under which rapid reversal of SSRI-induced anxiety can be modeled in animals using the NIH test.

Secondary Prevention of Chronic PTSD by Early and Short-Term Administration of Escitalopram: A Prospective Randomized, Placebo-Controlled, Double-Blind Trial.

PubMed

Zohar, Joseph; Fostick, Leah; Juven-Wetzler, Alzabeta; Kaplan, Zeev; Shalev, Hadar; Schreiber, Gavriel; Miroshnik, Natalie; Shalev, Arieh Y; Stein, Dan J; Seedat, Soraya; Suliman, Sharain; Klein, Ehud

Prospective studies have not identified a viable pharmacologic strategy for secondary prevention of posttraumatic stress disorder (PTSD). The authors examined whether preventive intervention via early and short-term administration of a selective serotonin reuptake inhibitor (SSRI), within 1 month of exposure to a traumatic event (before diagnosis of PTSD could be made), may reduce the severity of PTSD symptoms according to DSM-IV at 13 months' follow-up. Over 25,000 screening calls to patients referred to an emergency department for a traumatic event performed between June 2006 and December 2008 yielded 353 participants who were recruited within the month following a traumatic event . Participants were randomly assigned in a double-blind design to escitalopram (n = 176) or placebo (n = 177). The per-protocol analysis comprised 198 participants (escitalopram, n = 102; placebo, n = 96) who received treatment for 12 to 24 weeks and were available for follow-up at week 56. The primary outcome measure, the Clinician Administered PTSD Scale (CAPS), revealed no prevention effect. However, a secondary outcome, the Pittsburgh Sleep Quality Inventory (PSQI), showed better results for the SSRI group than for the placebo group. For a subset of participants who experienced intentional trauma (missile attacks, rape, or physical assault; n = 50), the prevention effect was found on both primary and secondary measures (CAPS, PSQI and measures of depression and global illness severity). Early and short-term administration of escitalopram was not shown to prevent PTSD, although it did improve sleep quality. In a subgroup of participants who experienced intentional trauma, however, this early-treatment approach may be effective as secondary prevention. This large study is the first to investigate the preventive effect of early administration of escitalopram on PTSD. It highlights the relevance of the type of trauma (intentional vs unintentional) to the outcome. ClinicalTrials.gov identifier: NCT00300313​​. © Copyright 2018 Physicians Postgraduate Press, Inc.

Involvement of 5-HT3 receptors in the action of vortioxetine in rat brain: Focus on glutamatergic and GABAergic neurotransmission.

PubMed

Riga, Maurizio S; Sánchez, Connie; Celada, Pau; Artigas, Francesc

2016-09-01

The antidepressant vortioxetine is a 5-HT3-R, 5-HT7-R and 5-HT1D-R antagonist, 5-HT1B-R partial agonist, 5-HT1A-R agonist, and serotonin (5-HT) transporter (SERT) inhibitor. Vortioxetine occupies all targets at high therapeutic doses and only SERT and 5-HT3-R at low doses. Vortioxetine increases extracellular monoamine concentrations in rat forebrain more than selective serotonin reuptake inhibitors (SSRI) and shows pro-cognitive activity in preclinical models. Given its high affinity for 5-HT3-R (Ki = 3.7 nM), selectively expressed in GABA interneurons, we hypothesized that vortioxetine may disinhibit glutamatergic and monoaminergic neurotransmission following 5-HT3-R blockade. Here we assessed vortioxetine effect on pyramidal neuron activity and extracellular 5-HT concentration using in vivo extracellular recordings of rat medial prefrontal cortex (mPFC) pyramidal neurons and microdialysis in mPFC and ventral hippocampus (vHPC). Vortioxetine, but not escitalopram, increased pyramidal neuron discharge in mPFC. This effect was prevented by SR57227A (5-HT3-R agonist) and was mimicked by ondansetron (5-HT3-R antagonist) and by escitalopram/ondansetron combinations. In microdialysis experiments, ondansetron augmented the 5-HT-enhancing effect of escitalopram in mPFC and vHPC. Local ondansetron in vHPC augmented escitalopram effect, indicating the participation of intrinsic mechanisms. Since 5-HT neurons express GABAB receptors, we examined their putative involvement in controlling 5-HT release after 5-HT3-R blockade. Co-perfusion of baclofen (but not muscimol) reversed the increased 5-HT levels produced by vortioxetine and escitalopram/ondansetron combinations in vHPC. The present results suggest that vortioxetine increases glutamatergic and serotonergic neurotransmission in rat forebrain by blocking 5-HT3 receptors in GABA interneurons. Copyright © 2016. Published by Elsevier Ltd.

Effects of escitalopram prophylaxis during antiviral treatment for chronic hepatitis C in patients with a history of intravenous drug use and depression.

PubMed

Hotho, Daphne M; Bezemer, Geert; Hansen, Bettina E; Van Gool, Arthur R; de Knegt, Robert J; Janssen, Harry L A; Veldt, Bart J

2014-10-01

We aimed to identify those patients with hepatitis C virus who benefit most from prophylactic treatment with selective serotonin reuptake inhibitors (SSRIs) during antiviral therapy. We performed post hoc analyses on a prospective randomized controlled trial (n = 79) of escitalopram versus placebo during antiviral therapy with pegylated interferon and ribavirin, conducted between August 2005 and June 2008. Our primary outcome measure was the association of baseline characteristics with the development of depression and/or depressive symptoms. Further, we studied effects of prophylactic escitalopram on depressive symptoms. Presence of a major depression was diagnosed using Mini-International Neuropsychiatric Interview (MINI), a short, structured interview used to diagnose DSM-IV-TR and ICD-10 disorders. Depressive symptoms were monitored during treatment by using the depression scale of Symptom Checklist-90 (SCL-90), Montgomery-Asberg Depression Rating Scale (MADRS), and Beck Depression Inventory (BDI) at baseline and weeks 4, 12, and 24 of antiviral therapy. Depression occurred in 14 patients receiving placebo and in 5 patients receiving escitalopram (Pearson χ², P = .01). Combination of history of depression and intravenous drug use was associated with depression (odds ratio = 12.60; 95% CI, 2.47-64.34; P < .01). Moreover, treatment with selective serotonin reuptake inhibitor compared to placebo was associated with a significant reduction in estimated mean depressive symptoms measured by SCL-90 (P = .03) and BDI (P = .048), but not with MADRS (P = .64). Patients infected by hepatitis C virus with a history of depression and intravenous drug use carry the highest risk to develop interferon-induced depression. In this subset of patients, prophylaxis with escitalopram results in the most substantial decrease of interferon-induced depressive symptoms on the SCL-90 depression scale and the BDI. © Copyright 2014 Physicians Postgraduate Press, Inc.

Relapse prevention and residual symptoms: a closer analysis of placebo-controlled continuation studies with escitalopram in major depressive disorder, generalized anxiety disorder, social anxiety disorder, and obsessive-compulsive disorder.

PubMed

Bech, Per; Lönn, Sara L; Overø, Kerstin F

2010-02-01

Analyses of data from 4 relapse-prevention studies with escitalopram were conducted in order to compare patients with and without residual symptoms with regard to relapse rates and global illness during double-blind, 24-week continuation periods. Clinical Global Impressions-Severity of Illness scores and relapse status in 4 studies published from 2005 to 2007, 1 each in major depressive disorder (MDD), generalized anxiety disorder, social anxiety disorder, and obsessive-compulsive disorder (OCD), were analyzed using mixed-effects model repeated measures as a function of Montgomery-Asberg Depression Rating Scale (MADRS) scores on items 1, 3, and 7 at randomization. All studies showed a statistically significant (P < .0001) standardized effect size of about 0.7 for escitalopram versus placebo, with a number needed to treat approximately 4. Patients with residual symptoms (MADRS score > 0) and without residual symptoms (MADRS score = 0) at the start of continuation treatment were defined by how patients scored on 3 core items of the MADRS: depressed mood (observed), inner or psychic tension, and lassitude. At randomization, patients with a residual symptom were globally more ill than patients without such a symptom. Patients who did not continue active treatment worsened, even if they were initially free of a residual symptom. In contrast, patients who continued receiving escitalopram remained stable or further improved, regardless of residual symptoms or diagnosis. No clear picture emerged regarding whether patients with residual symptoms had a higher relapse rate. The presence of residual symptoms is associated with significantly worse overall illness severity in all 4 diagnostic groups and with a higher (although not significantly) risk of relapse for patients with MDD or OCD. The greatest difference in all of the studies was between patients treated with escitalopram (relapse rates ~ 20%) and placebo (relapse rates of about 50%). Copyright 2010 Physicians Postgraduate Press, Inc.

Serotonin syndrome caused by drug to drug interaction between escitalopram and dextromethorphan.

PubMed

Dy, Prudence; Arcega, Victor; Ghali, Wael; Wolfe, Winifred

2017-08-07

A 63-year-old woman with a history of long-standing depression, maintained on escitalopram, presented with altered mental status. Patient had recently been prescribed dextromethorphan-promethazine cough syrup 2 weeks prior for an upper respiratory tract infection. On admission, she was lethargic and obtunded and found to have inducible myoclonus on examination. The rest of her physical exam was unremarkable. Pertinent lab and imaging findings showed QTc prolongation on ECG, negative electroencephalogram and CT head findings, essentially normal blood tests and a negative toxicology screen. The patient was admitted to the step down unit for close observation; both escitalopram and the cough syrup were suspended and was supportively managed. Overnight the patient's mental status improved and the serial EcGs showed resolution of the prolonged QTc. Patient was discharged home without further complication. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Glycine and a Glycine Dehydrogenase (GLDC) SNP as Citalopram/Escitalopram Response Biomarkers in Depression: Pharmacometabolomics-informed Pharmacogenomics

PubMed Central

Ji, Yuan; Hebbring, Scott; Zhu, Hongjie; Jenkins, Gregory D; Biernacka, Joanna; Snyder, Karen; Drews, Maureen; Fiehn, Oliver; Zeng, Zhaobang; Schaid, Daniel; Mrazek, David A.; Kaddurah-Daouk, Rima; Weinshilboum, Richard M.

2011-01-01

Major depressive disorder (MDD) is a common psychiatric disease. Selective serotonin reuptake inhibitors (SSRIs) are an important class of drugs used to treat MDD. However, many patients do not respond adequately to SSRI therapy. We used a pharmacometabolomics-informed pharmacogenomic research strategy to identify citalopram/escitalopram treatment outcome biomarkers. Metabolomic assay of plasma samples from 20 escitalopram remitters and 20 non-remitters showed that glycine was negatively associated with treatment outcome (p=0.0054). That observation was pursued by genotyping tag single nucleotide polymorphisms (SNPs) for genes encoding glycine synthesis and degradation enzymes using 529 DNA samples from SSRI-treated MDD patients. The rs10975641 SNP in the glycine dehydrogenase gene was associated with treatment outcome phenotypes. Rs10975641 was then genotyped and was significant (p=0.02) in DNA from 1245 MDD patients in the STAR*D depression study. These results highlight both a possible role for glycine in SSRI response and the use of pharmacometabolomics to “inform” pharmacogenomics. PMID:21107318

Escitalopram treatment for premature ejaculation has a negative effect on semen parameters.

PubMed

Koyuncu, H; Serefoglu, E C; Yencilek, E; Atalay, H; Akbas, N B; Sarıca, K

2011-01-01

The aim of this study was to determine the impact of long-term escitalopram treatment on semen parameters of patients with lifelong premature ejaculation (PE). Between November 2008 and January 2010, patients admitted to urology outpatient clinic with a self-reported complaint of PE were evaluated. Medical and sexual history of patients were recorded and patients with lifelong PE (a total of 25 patients) who met the International Society of Sexual Medicine definition were asked to record their intravaginal ejaculatory latency time (IELT) for 1 month, complete Premature Ejaculation Diagnostic Tool (PEDT) questionnaire and give semen samples. Afterwards, patients received 10 mg escitalopram daily for 12 weeks and were invited for control visits at first and third month of treatment. During control visits, PEDT was administered again whereas IELTs were recorded and semen samples were re-examined. PEDT scores, arithmetic means of IELTs and results of semen analyses, which were recorded at baseline, first and third month were compared. At the third month of treatment, a significant increase in mean IELTs and a significant decrease in PEDT scores were detected. However there was a significant decrease in sperm concentration, motility and morphology when compared with the baseline semen measures. Daily escitalopram treatment effects the semen parameters of patients with lifelong PE. Further investigations with larger series are needed to see whether other serotonin reuptake inhibitors have similar side effects and to expose the exact mechanism underlying it. Different treatment modalities should be suggested to patients who desire fertility.

Effects of Escitalopram on Autonomic Function in Posttraumatic Stress Disorder Among Veterans of Operations Enduring Freedom and Iraqi Freedom (OEF/OIF).

PubMed

Ramaswamy, Sriram; Selvaraj, Vithyalakshmi; Driscoll, David; Madabushi, Jayakrishna S; Bhatia, Subhash C; Yeragani, Vikram

2015-01-01

Posttraumatic stress disorder is a chronic, debilitating condition that has become a growing concern among combat veterans. Previous research suggests that posttraumatic stress disorder disrupts normal autonomic responding and may increase the risk of cardiovascular disease and mortality. Measures of heart rate variability and QT interval variability have been used extensively to characterize sympathetic and parasympathetic influences on heart rate in a variety of psychiatric populations. The objective of this study was to better understand the effects of pharmacological treatment on autonomic reactivity in posttraumatic stress disorder. A 12-week, Phase IV, prospective, open-label trial of escitalopram in veterans with combat-related posttraumatic stress disorder and comorbid depression. An outpatient mental health clinic at a Veterans Affairs Medical Center. Eleven male veterans of Operations Enduring Freedom and Iraqi Freedom diagnosed with posttraumatic stress disorder and comorbid depression. Autonomic reactivity was measured by examining heart rate variability and QT interval variability. Treatment safety and efficacy were also evaluated pre- and post-treatment. We observed a reduction in posttraumatic stress disorder and depression symptoms from pre- to post-treatment, and escitalopram was generally well tolerated in our sample. In addition, we observed a decrease in high frequency heart rate variability and an increase in QT variability, indicating a reduction in cardiac vagal function and heightened sympathetic activation. These findings suggest that escitalopram treatment in patients with posttraumatic stress disorder and depression can trigger changes in autonomic reactivity that may adversely impact cardiovascular health.

Association between personality traits and Escitalopram treatment efficacy in panic disorder.

PubMed

Võhma, Ülle; Raag, Mait; Tõru, Innar; Aluoja, Anu; Maron, Eduard

2017-08-01

There is strong evidence to suggest that personality factors may interact with the development and clinical expression of panic disorder (PD). A greater understanding of these relationships may have important implications for clinical practice and implications for searching reliable predictors of treatment outcome. The study aimed to examine the effect of escitalopram treatment on personality traits in PD patients, and to identify whether the treatment outcome could be predicted by any personality trait. A study sample consisting of 110 outpatients with PD treated with 10-20 mg/day of escitalopram for 12 weeks. The personality traits were evaluated before and after 12 weeks of medication by using the Swedish universities Scales of Personality (SSP). Although almost all personality traits on the SSP measurement were improved after 12 weeks of medication in comparison with the baseline scores, none of these changes reached a statistically significant level. Only higher impulsivity at baseline SSP predicted non-remission to 12-weeks treatment with escitalopram; however, this association did not withstand the Bonferroni correction in multiple comparisons. All patients were treated in a naturalistic way using an open-label drug, so placebo responses cannot be excluded. The sample size can still be considered not large enough to reveal statistically significant findings. Maladaptive personality disposition in patients with PD seems to have a trait character and shows little trend toward normalization after 12-weeks treatment with the antidepressant, while the association between impulsivity and treatment response needs further investigation.

Mapping the effect of escitalopram treatment on amplitude of low-frequency fluctuations in patients with depression: a resting-state fMRI study.

PubMed

Wang, Li; Li, Xueni; Li, Ke; Su, Yunai; Zeng, Yawei; Zhang, Qinge; Wang, Gang; Jin, Zhen; Kong, Qingmei; Si, Tianmei

2017-02-01

Antidepressant medications represent the most common treatment option for major depressive disorder (MDD), but the neuro-psychological mechanisms by which antidepressants act to improve depressive symptoms remain under-specified. We designed this study to assess the effects of escitalopram treatment on spontaneous brain activity of MDD patients using functional magnetic resonance imaging (fMRI). Twenty first-episode drug-naive MDD patients received resting-state fMRI scans before and after 8 weeks of treatment with a selective serotonin reuptake inhibitor - escitalopram. Twenty age- and gender-matched healthy controls were also scanned twice with an 8-week interval. The fractional amplitude of low-frequency fluctuation (fALFF) was used to characterize the spontaneous brain activity. The analysis of covariance (ANCOVA) was performed to determine treatment-related changes in fALFF. The symptoms were significantly improved in MDD patients after treatment. We observed significant group-by-time interaction on fALFF in the left dorsomedial prefrontal cortex, the right middle frontal gyrus, and the left putamen. Post-hoc analyses showed that the fALFF values in these regions were significantly higher in the MDD patients compared to healthy controls at baseline and were reduced after treatment. The findings suggest that abnormalities in the brain areas involved in emotional processing and regulation could be normalized by effective antidepressant treatment with escitalopram in the MDD patients and free of a task situation.

Contribution of dietary oxalate to urinary oxalate excretion

NASA Technical Reports Server (NTRS)

Holmes, R. P.; Goodman, H. O.; Assimos, D. G.

2001-01-01

BACKGROUND: The amount of oxalate excreted in urine has a significant impact on calcium oxalate supersaturation and stone formation. Dietary oxalate is believed to make only a minor (10 to 20%) contribution to the amount of oxalate excreted in urine, but the validity of the experimental observations that support this conclusion can be questioned. An understanding of the actual contribution of dietary oxalate to urinary oxalate excretion is important, as it is potentially modifiable. METHODS: We varied the amount of dietary oxalate consumed by a group of adult individuals using formula diets and controlled, solid-food diets with a known oxalate content, determined by a recently developed analytical procedure. Controlled solid-food diets were consumed containing 10, 50, and 250 mg of oxalate/2500 kcal, as well as formula diets containing 0 and 180 mg oxalate/2500 kcal. Changes in the content of oxalate and other ions were assessed in 24-hour urine collections. RESULTS: Urinary oxalate excretion increased as dietary oxalate intake increased. With oxalate-containing diets, the mean contribution of dietary oxalate to urinary oxalate excretion ranged from 24.4 +/- 15.5% on the 10 mg/2500 kcal/day diet to 41.5 +/- 9.1% on the 250 mg/2500 kcal/day diet, much higher than previously estimated. When the calcium content of a diet containing 250 mg of oxalate was reduced from 1002 mg to 391 mg, urinary oxalate excretion increased by a mean of 28.2 +/- 4.8%, and the mean dietary contribution increased to 52.6 +/- 8.6%. CONCLUSIONS: These results suggest that dietary oxalate makes a much greater contribution to urinary oxalate excretion than previously recognized, that dietary calcium influences the bioavailability of ingested oxalate, and that the absorption of dietary oxalate may be an important factor in calcium oxalate stone formation.

Oxalate absorption and endogenous oxalate synthesis from ascorbate in calcium oxalate stone formers and non-stone formers.

PubMed

Chai, Weiwen; Liebman, Michael; Kynast-Gales, Susan; Massey, Linda

2004-12-01

Increased rates of either oxalate absorption or endogenous oxalate synthesis can contribute to hyperoxaluria, a primary risk factor for the formation of calcium oxalate-containing kidney stones. This study involves a comparative assessment of oxalate absorption and endogenous oxalate synthesis in subpopulations of stone formers (SFs) and non-stone formers (NSFs) and an assessment of the effect of ascorbate supplementation on oxalate absorption and endogenous oxalate synthesis. Twenty-nine individuals with a history of calcium oxalate kidney stones (19 men, 10 women) and 19 age-matched NSFs (8 men, 11 women) participated in two 6-day controlled feeding experimental periods: ascorbate-supplement (2 g/d) and no-supplement treatments. An oxalate load consisting of 118 mg of unlabeled oxalate and 18 mg of 13C2 -oxalic acid was administered the morning of day 6 of each experimental period. Mean 13C2 -oxalic acid absorption averaged across the ascorbate and no-supplement treatments was significantly greater in SFs (9.9%) than NSFs (8.0%). SFs also had significantly greater 24-hour post-oxalate load urinary total oxalate and endogenous oxalate levels with both treatments. Twenty-four-hour urinary total oxalate level correlated strongly with both 13C2 -oxalic acid absorption (SFs, r = 0.76; P < 0.01; NSFs, r = 0.62; P < 0.01) and endogenous oxalate synthesis (SFs, r = 0.95; P < 0.01; NSFs, r = 0.92; P < 0.01). SFs are characterized by greater rates of both oxalate absorption and endogenous oxalate synthesis, and both these factors contribute to the hyperoxaluric state. The finding that ascorbate supplementation increased urinary total and endogenous oxalate levels suggested that this practice is a risk factor for individuals predisposed to kidney stones.

Diet, but not oral probiotics, effectively reduces urinary oxalate excretion and calcium oxalate supersaturation.

PubMed

Lieske, John C; Tremaine, William J; De Simone, Claudio; O'Connor, Helen M; Li, Xujian; Bergstralh, Eric J; Goldfarb, David S

2010-12-01

We examined the effect of a controlled diet and two probiotic preparations on urinary oxalate excretion, a risk factor for calcium oxalate kidney stone formation, in patients with mild hyperoxaluria. Patients were randomized to a placebo, a probiotic, or a synbiotic preparation. This tested whether these probiotic preparations can increase oxalate metabolism in the intestine and/or decrease oxalate absorption from the gut. Patients were maintained on a controlled diet to remove the confounding variable of differing oxalate intake from food. Urinary oxalate excretion and calcium oxalate supersaturation on the controlled diet were significantly lower compared with baseline on a free-choice diet. Neither study preparation reduced urinary oxalate excretion nor calcium oxalate supersaturation. Fecal lactobacilli colony counts increased on both preparations, whereas enterococcal and yeast colony counts were increased on the synbiotic. Total urine volume and the excretion of oxalate and calcium were all strong independent determinants of urinary calcium oxalate supersaturation. Hence, dietary oxalate restriction reduced urinary oxalate excretion, but the tested probiotics did not influence urinary oxalate levels in patients on a restricted oxalate diet. However, this study suggests that dietary oxalate restriction is useful for kidney stone prevention.

Highly Enantioselective Rhodium-Catalyzed Addition of Arylboroxines to Simple Aryl Ketones: Efficient Synthesis of Escitalopram.

PubMed

Huang, Linwei; Zhu, Jinbin; Jiao, Guangjun; Wang, Zheng; Yu, Xingxin; Deng, Wei-Ping; Tang, Wenjun

2016-03-24

Highly enantioselective additions of arylboroxines to simple aryl ketones have been achieved for the first time with a Rh/(R,R,R,R)-WingPhos catalyst, thus providing a range of chiral diaryl alkyl carbinols with excellent ee values and yields. (R,R,R,R)-WingPhos has been proven to be crucial for the high reactivity and enantioselectivity. The method has enabled a new, concise, and enantioselective synthesis of the antidepressant drug escitalopram. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Role of cellular oxalate in oxalate clearance of patients with calcium oxalate monohydrate stone formation and normal controls.

PubMed

Oehlschläger, Sven; Fuessel, Susanne; Meye, Axel; Herrmann, Jana; Froehner, Michael; Albrecht, Steffen; Wirth, Manfred P

2009-03-01

To examine the cellular, plasma, and urinary oxalate and erythrocyte oxalate flux in patients with calcium oxalate monohydrate (COM) stone formation vs normal controls. Pathologic oxalate clearance in humans is mostly integrated in calcium oxalate stone formation. An underlying cause of deficient oxalate clearance could be defective transmembrane oxalate transport, which, in many tissues, is regulated by an anion exchanger (SLC26). We studied 2 groups: 40 normal controls and 41 patients with COM stone formation. Red blood cells were divided for cellular oxalate measurement and for resuspension in a buffered solution (pH 7.40); 0.1 mmol/L oxalate was added. The supernatant was measured for oxalate immediately and 1 hour after incubation. The plasma and urinary oxalate were analyzed in parallel. The mean cellular oxalate concentrations were significantly greater in the normal controls (5.25 +/- 0.47 micromol/L) than in those with COM stone formation (2.36 +/- 0.28 micromol/L; P < .01). The mean urinary oxalate concentrations were significantly greater in those with COM stone formation (0.31 +/- 0.02 mmol/L) than in the controls (0.24 +/- 0.02 mmol/L; P < .01). The cellular oxalate concentrations correlated significantly with the plasma (r = 0.49-0.63; P < .01) and urinary oxalate (r = -0.29-0.41; P < .03) concentrations in both groups. The plasma oxalate concentrations correlated significantly with the urinary oxalate concentrations (r = -0.30; P < .03) in the controls and with the erythrocyte oxalate flux (r = 0.25; P < .05) in those with COM stone formation. Our data implicate the presence of a cellular oxalate buffer to stabilize plasma and urinary oxalate concentrations in normal controls.

Double-blind, randomized comparison of memantine and escitalopram for the treatment of major depressive disorder comorbid with alcohol dependence.

PubMed

Muhonen, Leea H; Lönnqvist, Jouko; Juva, Kati; Alho, Hannu

2008-03-01

The aim of the study was to evaluate possible new treatments for major depressive disorder in patients with comorbid alcohol dependence in a municipal alcohol treatment unit. The efficacy of memantine, a noncompetitive glutamate N-methyl-D-aspartate (NMDA)-receptor blocker used for the treatment of moderate to severe Alzheimer's disease, was compared with that of escitalopram, a selective serotonin reuptake inhibitor antidepressant. Eighty alcohol-dependent outpatients with major depressive disorder (DSM-IV criteria) seeking treatment from municipal alcohol treatment clinics in Helsinki, Finland, were randomly assigned 1:1 to receive memantine 20 mg/day or escitalopram 20 mg/day. During the study period, patients continued their routine treatment at the clinics. Abstinence was not required. Concomitant interventions or imposed treatment goals were not offered by the study physician. The patients returned to the treatment clinics at weeks 1, 2, 4, 12, and 26 for data collection and for medication checking and dispensing. Outcome measures were the Montgomery-Asberg Depression Rating Scale (MADRS) and Beck Depression Inventory-II for depression, Hamilton Rating Scale for Anxiety (HAM-A) and Beck Anxiety Inventory for anxiety, Consortium to Establish a Registry for Alzheimer's Disease test battery for cognitive functions, and Social and Occupational Functioning Assessment Scale for social and occupational functions and quality-of-life measures. Twenty-nine patients in each group completed the study. All primary and secondary outcome statistical analyses were performed by an independent source for intent-to-treat populations, which included all patients randomly assigned to treatment. The study was conducted from December 2004 to May 2006. Both treatments significantly reduced the baseline level of depression and anxiety according to MADRS and HAM-A, which were the primary measures (p < .0001). There was no significant difference between the memantine and escitalopram groups. Assessed cognitive functioning scores were primarily within the normative range and were unchanged in both groups. Quality-of-life outcomes equally improved in both treatment groups. These data provide new evidence for the safety and potential efficacy of memantine and escitalopram for major depressive disorder in patients with comorbid alcohol dependence. ClinicalTrials.gov identifier NCT00368862.

Dietary hyperoxaluria is not reduced by treatment with lactic acid bacteria

PubMed Central

2013-01-01

Background Secondary hyperoxaluria either based on increased intestinal absorption of oxalate (enteric), or high oxalate intake (dietary), is a major risk factor of calcium oxalate urolithiasis. Oxalate-degrading bacteria might have beneficial effects on urinary oxalate excretion resulting from decreased intestinal oxalate concentration and absorption. Methods Twenty healthy subjects were studied initially while consuming a diet normal in oxalate. Study participants were then placed on a controlled oxalate-rich diet for a period of 6 weeks. Starting with week 2 of the oxalate-rich diet, participants received 2.6 g/day of a lactic acid bacteria preparation for 5 weeks. Finally, subjects were examined 4 weeks after treatment while consuming again a normal-oxalate diet. Participants provided weekly 24-hour urine specimens. Analyses of blood samples were performed before and at the end of treatment. Results Urinary oxalate excretion increased significantly from 0.354 ± 0.097 at baseline to 0.542 ± 0.163 mmol/24 h under the oxalate-rich diet and remained elevated until the end of treatment, as did relative supersaturation of calcium oxalate. Plasma oxalate concentration was significantly higher after 5 weeks of treatment compared to baseline. Four weeks after treatment, urinary oxalate excretion and relative supersaturation of calcium oxalate fell to reach initial values. Conclusions Persistent dietary hyperoxaluria and increased plasma oxalate concentration can already be induced in healthy subjects without disorders of oxalate metabolism. The study preparation neither reduced urinary oxalate excretion nor plasma oxalate concentration. The preparation may be altered to select for lactic acid bacteria strains with the highest oxalate-degrading activity. PMID:24330782

The bioavailability of oxalate from Oca (Oxalis tuberosa).

PubMed

Albihn, P B; Savage, G P

2001-08-01

It is believed that soluble oxalate has higher bioavailability than insoluble oxalate. Oca (Oxalis tuberosa) is moderately high in oxalate and contains oxalate in soluble form only. We estimated the bioavailability of oxalate in oca based on the urinary excretion of oxalate after oxalate loading with oca to estimate the bioavailability of oxalate in oca. We also clarified whether bioavailability differs in various oxalate loads from the same food source and studied the effect of an additional calcium source on the bioavailability of oxalate from oca. Four men and 4 women ingested 50, 100 and 150 gm. oca as well as 100 gm. oca with 100 gm. sour cream. Oxalate was measured in a 6-hour urine sample from each volunteer. The mean bioavailability of oxalate from oca plus or minus standard deviation was 1.44% +/- 1.31% during the 6-hour period after intake. There was no significant difference in oxalate bioavailability among oxalate intake levels in this study, although oca consumption with sour cream significantly decreased the uptake of oxalate (p <0.01). The variation in bioavailability among individuals was high in our study. The bioavailability of oxalate in oca appears to be similar to that in spinach. However, bioavailability varies among individuals and depends on other constituents of a combined meal.

Apathy in late-life depression: common, persistent, and disabling.

PubMed

Yuen, Genevieve S; Bhutani, Saumya; Lucas, Bryony J; Gunning, Faith M; AbdelMalak, Bassem; Seirup, Joanna K; Klimstra, Sibel A; Alexopoulos, George S

2015-05-01

The aims of this study were to examine: (1) the relationship between apathy and disability in late-life depression, and (2) the functional significance of improvement in apathy following escitalopram treatment in terms of its relationship to disability. Subjects were 71 non-demented elderly with non-psychotic major depression. After a 2-week single-blind placebo period, subjects who had Hamilton Depression Rating Scale (HDRS) ≥ 18 received escitalopram 10 mg daily for 12 weeks. Apathy and disability were assessed with the Apathy Evaluation Scale (AES) and the World Health Organization Disability Assessment Scale II (WHODAS), respectively. These measures and the HDRS were administered at baseline and again following 12 weeks of treatment. At baseline, 38% of depressed subjects had significant apathy (AES ≥ 36.5). Severity of apathy at baseline significantly correlated with severity of disability. In a multivariate regression model, baseline severity of apathy, but not the overall depressive syndrome (HDRS), significantly correlated with baseline disability. Following escitalopram treatment, improvement in apathy significantly correlated with improvement in disability measures, while change in the rest of the depressive syndrome did not. The overall change in apathy and disability in response to escitalopram treatment was significant but small. Apathy is common in late-life depression and is associated with disability above and beyond the influence of other depressive symptoms. Given the strong relationship between apathy and disability, understanding the neurobiology of apathy and developing treatments for apathy may improve the functional outcomes of late-life depression. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Treatment of cannabis dependence using escitalopram in combination with cognitive-behavior therapy: a double-blind placebo-controlled study.

PubMed

Weinstein, A M; Miller, H; Bluvstein, I; Rapoport, E; Schreiber, S; Bar-Hamburger, R; Bloch, M

2014-01-01

Cannabis is the most frequently used illegal substance in the United States and Europe. There is a dramatic increase in the demand for treatment for cannabis dependence. Cannabis users frequently have co-morbid mood symptoms, especially depression and anxiety, and regular cannabis users may self-medicate for such symptoms. We report a double-blind, placebo-controlled treatment study, for the prevention of cannabis use in cannabis-dependent individuals. Regular cannabis-dependent users (n = 52) were treated for 9 weeks with weekly cognitive-behavior and motivation-enhancement therapy sessions together with escitalopram 10 mg/day. Urine samples were collected to monitor delta-9 tetrahydrocannabinol (THC) during treatment and questionnaires were administered to assess anxiety and depression. We observed a high rate of dropout (50%) during the 9-week treatment program. Fifty-two patients were included in the intention-to-treat analysis. Of these, ten (19%) remained abstinent after 9 weeks of treatment as indicated by negative urine samples for THC. Escitalopram provided no advantage over placebo in either abstinence rates from cannabis or anxiety and depression scores during the withdrawal and abstinent periods. Escitalopram treatment does not provide an additional benefit either for achieving abstinence, or for the treatment of the cannabis withdrawal syndrome. Due to limitations of our study, namely, a high dropout rate and effects of low abstinence rates on measures of anxiety, depression and withdrawal, it is premature to conclude that selective serotonin reuptake inhibitors are not effective for treatment of the cannabis withdrawal syndrome.

Combining clinical variables to optimize prediction of antidepressant treatment outcomes.

PubMed

Iniesta, Raquel; Malki, Karim; Maier, Wolfgang; Rietschel, Marcella; Mors, Ole; Hauser, Joanna; Henigsberg, Neven; Dernovsek, Mojca Zvezdana; Souery, Daniel; Stahl, Daniel; Dobson, Richard; Aitchison, Katherine J; Farmer, Anne; Lewis, Cathryn M; McGuffin, Peter; Uher, Rudolf

2016-07-01

The outcome of treatment with antidepressants varies markedly across people with the same diagnosis. A clinically significant prediction of outcomes could spare the frustration of trial and error approach and improve the outcomes of major depressive disorder through individualized treatment selection. It is likely that a combination of multiple predictors is needed to achieve such prediction. We used elastic net regularized regression to optimize prediction of symptom improvement and remission during treatment with escitalopram or nortriptyline and to identify contributing predictors from a range of demographic and clinical variables in 793 adults with major depressive disorder. A combination of demographic and clinical variables, with strong contributions from symptoms of depressed mood, reduced interest, decreased activity, indecisiveness, pessimism and anxiety significantly predicted treatment outcomes, explaining 5-10% of variance in symptom improvement with escitalopram. Similar combinations of variables predicted remission with area under the curve 0.72, explaining approximately 15% of variance (pseudo R(2)) in who achieves remission, with strong contributions from body mass index, appetite, interest-activity symptom dimension and anxious-somatizing depression subtype. Escitalopram-specific outcome prediction was more accurate than generic outcome prediction, and reached effect sizes that were near or above a previously established benchmark for clinical significance. Outcome prediction on the nortriptyline arm did not significantly differ from chance. These results suggest that easily obtained demographic and clinical variables can predict therapeutic response to escitalopram with clinically meaningful accuracy, suggesting a potential for individualized prescription of this antidepressant drug. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Comparative efficacy, acceptability, and safety of medicinal, cognitive-behavioral therapy, and placebo treatments for acute major depressive disorder in children and adolescents: a multiple-treatments meta-analysis.

PubMed

Ma, Dongfeng; Zhang, Zhijun; Zhang, Xiangrong; Li, Lingjiang

2014-06-01

New generation antidepressant therapies, including serotonin-norepinephrine reuptake inhibitor (SNRIs) and selective serotonin reuptake inhibitors (SSRIs) were introduced in the late 1980s; however, few comprehensive studies compared the benefits and risks of various contemporary treatments for major depressive disorder (MDD) in pediatric patients. Multiple-treatments meta-analysis (MTM) was conducted to assess efficacy, acceptability, and safety of contemporary interventions in children and adolescents with MDD. Cochrane Library, AMED, CINAHL, EMBASE, LiLACS, MEDLINE, PSYCINFO, PSYNDEX, and Journal of Medicine and Pharmacy databases were searched for randomized controlled trials (RCTs) comparing medicinal interventions (citalopram, escitalopram, fluoxetine, mirtazapine, paroxetine, sertraline, venlafaxine), cognitive behavioral therapy (CBT), combined fluoxetine with CBT, and placebo treatment for acute MDD from January 1988 to March 2013. Treatment success, dropout rate, and suicidal ideation/attempt outcomes were measured. Bayesian methods were used to conduct a MTM including age and funding subgroups. A total of 21 RCTs (4969 participants) were identified. Combined fluoxetine/CBT exhibited the highest efficacy, with fluoxetine alone superior to CBT, paroxetine, sertraline, citalopram, escitalopram, and placebo treatment. Sertraline, paroxetine, escitalopram, and venlafaxine showed superior acceptability to fluoxetine and combined fluoxetine/CBT. Combined fluoxetine/CBT combination was less safe, though CBT was safer than fluoxetine alone. Combined fluoxetine/CBT, fluoxetine, and mirtazapine exhibited the highest efficacy; sertraline, escitalopram, venlafaxine, and paroxetine were the best tolerated; and mirtazapine and venlafaxine were the safest. Sertraline and mirtazapine exhibited optimally balanced efficacy, acceptability, and safety for first-line acute treatment of child and adolescent MDD.

Treatment with escitalopram but not desipramine decreases escape latency times in a learned helplessness model using juvenile rats.

PubMed

Reed, Abbey L; Anderson, Jeffrey C; Bylund, David B; Petty, Frederick; El Refaey, Hesham; Happe, H Kevin

2009-08-01

The pharmacological treatment of depression in children and adolescents is different from that of adults due to the lack of efficacy of certain antidepressants in the pediatric age group. Our current understanding of why these differences occur is very limited. To develop more effective treatments, a juvenile animal model of depression was tested to validate it as a possible model to specifically study pediatric depression. Procedures for use with juvenile rats at postnatal day (PND) 21 and 28 were adapted from the adult learned helplessness model in which, 24 h after exposure to inescapable stress, animals are unable to remove themselves from an easily escapable stressor. Rats were treated for 7 days with either the selective serotonin reuptake inhibitor escitalopram at 10 mg/kg or the tricyclic antidepressant desipramine at 3, 10, or 15 mg/kg to determine if treatment could decrease escape latency times. Escitalopram treatment was effective at decreasing escape latency times in all ages tested. Desipramine treatment did not decrease escape latency times for PND 21 rats, but did decrease times for PND 28 and adult animals. The learned helplessness model with PND 21 rats predicts the efficacy of escitalopram and the lack of efficacy of desipramine seen in the treatment of pediatric depression. These findings suggest that the use of PND 21 rats in a modified learned helplessness procedure may be a valuable model of human pediatric depression that can predict pediatric antidepressant efficacy and be used to study antidepressant mechanisms involved in pediatric depression.

Origin of Urinary Oxalate

NASA Astrophysics Data System (ADS)

Holmes, Ross P.; Knight, John; Assimos, Dean G.

2007-04-01

Urinary oxalate is mostly derived from the absorption of ingested oxalate and endogenous synthesis. The breakdown of vitamin C may also contribute small amounts to the urinary oxalate pool. The amount of oxalate absorbed is influenced by the oxalate content of the diet, the concentrations of divalent cations in the gut, the presence of oxalate-degrading organisms, transport characteristics of the intestinal epithelium, and other factors associated with the intestinal environment. Knowledge of pathways associated with endogenous oxalate synthesis is limited. Urinary oxalate excretion can be modified using strategies that limit dietary oxalate absorption and the ingestion of oxalogenic substrates such as hydroxyproline.

Glycine and a glycine dehydrogenase (GLDC) SNP as citalopram/escitalopram response biomarkers in depression: pharmacometabolomics-informed pharmacogenomics.

PubMed

Ji, Y; Hebbring, S; Zhu, H; Jenkins, G D; Biernacka, J; Snyder, K; Drews, M; Fiehn, O; Zeng, Z; Schaid, D; Mrazek, D A; Kaddurah-Daouk, R; Weinshilboum, R M

2011-01-01

Major depressive disorder (MDD) is a common psychiatric disease. Selective serotonin reuptake inhibitors (SSRIs) are an important class of drugs used in the treatment of MDD. However, many patients do not respond adequately to SSRI therapy. We used a pharmacometabolomics-informed pharmacogenomic research strategy to identify citalopram/escitalopram treatment outcome biomarkers. Metabolomic assay of plasma samples from 20 escitalopram remitters and 20 nonremitters showed that glycine was negatively associated with treatment outcome (P = 0.0054). This observation was pursued by genotyping tag single-nucleotide polymorphisms (SNPs) for genes encoding glycine synthesis and degradation enzymes, using 529 DNA samples from SSRI-treated MDD patients. The rs10975641 SNP in the glycine dehydrogenase (GLDC) gene was associated with treatment outcome phenotypes. Genotyping for rs10975641 was carried out in 1,245 MDD patients in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, and its presence was significant (P = 0.02) in DNA taken from these patients. These results highlight a possible role for glycine in SSRI response and illustrate the use of pharmacometabolomics to "inform" pharmacogenomics.

Early increase in marker of neuronal integrity with antidepressant treatment of major depression: 1H-magnetic resonance spectroscopy of N-acetyl-aspartate.

PubMed

Taylor, Matthew J; Godlewska, Beata R; Norbury, Ray; Selvaraj, Sudhakar; Near, Jamie; Cowen, Philip J

2012-11-01

Increasing interest surrounds potential neuroprotective or neurotrophic actions of antidepressants. While growing evidence points to important early clinical and neuropsychological effects of antidepressants, the time-course of any effect on neuronal integrity is unclear. This study used magnetic resonance spectroscopy to assess effects of short-term treatment with escitalopram on N-acetyl-aspartate (NAA), a marker of neuronal integrity. Thirty-nine participants with major depression were randomly assigned to receive either 10 mg escitalopram or placebo daily in a double-blind, parallel group design. On the seventh day of treatment, PRESS data were obtained from a 30×30×20 mm voxel placed in medial frontal cortex. Age and gender-matched healthy controls who received no treatment were also scanned. Levels of NAA were significantly higher in patients treated with escitalopram than in either placebo-treated patients (p<0.01) or healthy controls (p<0.01). Our findings are consistent with the proposition that antidepressant treatment in depressed patients can produce early changes in neuronal integrity.

Estimation of the oxalate content of foods and daily oxalate intake

NASA Technical Reports Server (NTRS)

Holmes, R. P.; Kennedy, M.

2000-01-01

BACKGROUND: The amount of oxalate ingested may be an important risk factor in the development of idiopathic calcium oxalate nephrolithiasis. Reliable food tables listing the oxalate content of foods are currently not available. The aim of this research was to develop an accurate and reliable method to measure the food content of oxalate. METHODS: Capillary electrophoresis (CE) and ion chromatography (IC) were compared as direct techniques for the estimation of the oxalate content of foods. Foods were thoroughly homogenized in acid, heat extracted, and clarified by centrifugation and filtration before dilution in water for analysis. Five individuals consuming self-selected diets maintained food records for three days to determine their mean daily oxalate intakes. RESULTS: Both techniques were capable of adequately measuring the oxalate in foods with a significant oxalate content. With foods of very low oxalate content (<1.8 mg/100 g), IC was more reliable than CE. The mean daily intake of oxalate by the five individuals tested was 152 +/- 83 mg, ranging from 44 to 352 mg/day. CONCLUSIONS: CE appears to be the method of choice over IC for estimating the oxalate content of foods with a medium (>10 mg/100 g) to high oxalate content due to a faster analysis time and lower running costs, whereas IC may be better suited for the analysis of foods with a low oxalate content. Accurate estimates of the oxalate content of foods should permit the role of dietary oxalate in urinary oxalate excretion and stone formation to be clarified. Other factors, apart from the amount of oxalate ingested, appear to exert a major influence over the amount of oxalate excreted in the urine.

Probiotics and Other Key Determinants of Dietary Oxalate Absorption1

PubMed Central

Liebman, Michael; Al-Wahsh, Ismail A.

2011-01-01

Oxalate is a common component of many foods of plant origin, including nuts, fruits, vegetables, grains, and legumes, and is typically present as a salt of oxalic acid. Because virtually all absorbed oxalic acid is excreted in the urine and hyperoxaluria is known to be a considerable risk factor for urolithiasis, it is important to understand the factors that have the potential to alter the efficiency of oxalate absorption. Oxalate bioavailability, a term that has been used to refer to that portion of food-derived oxalate that is absorbed from the gastrointestinal tract (GIT), is estimated to range from 2 to 15% for different foods. Oxalate bioavailability appears to be decreased by concomitant food ingestion due to interactions between oxalate and coingested food components that likely result in less oxalic acid remaining in a soluble form. There is a lack of consensus in the literature as to whether efficiency of oxalate absorption is dependent on the proportion of total dietary oxalate that is in a soluble form. However, studies that directly compared foods of varying soluble oxalate contents have generally supported the proposition that the amount of soluble oxalate in food is an important determinant of oxalate bioavailability. Oxalate degradation by oxalate-degrading bacteria within the GIT is another key factor that could affect oxalate absorption and degree of oxaluria. Studies that have assessed the efficacy of oral ingestion of probiotics that provide bacteria with oxalate-degrading capacity have led to promising but generally mixed results, and this remains a fertile area for future studies. PMID:22332057

NALP3-mediated inflammation is a principal cause of progressive renal failure in oxalate nephropathy

PubMed Central

Knauf, Felix; Asplin, John R.; Granja, Ignacio; Schmidt, Insa M.; Moeckel, Gilbert; David, Rachel; Flavell, Richard A.; Aronson, Peter S.

2013-01-01

Oxalate nephropathy with renal failure is caused by multiple disorders causing hyperoxaluria due to either overproduction of oxalate (primary hyperoxaluria) or excessive absorption of dietary oxalate (enteric hyperoxaluria). To study the etiology of renal failure in crystal-induced kidney disease, we created a model of progressive oxalate nephropathy by feeding mice a diet high in soluble oxalate (high oxalate in the absence of dietary calcium). Renal histology was characterized by intratubular calcium-oxalate crystal deposition with an inflammatory response in the surrounding interstitium. Oxalate nephropathy was not found in mice fed a high oxalate diet that also contained calcium. NALP3, also known as cryopyrin, has been implicated in crystal-associated diseases such as gout and silicosis. Mice fed the diet high in soluble oxalate demonstrated increased NALP3 expression in the kidney. Nalp3-null mice were completely protected from the progressive renal failure and death that occurred in wild-type mice fed the diet high in soluble oxalate. NALP3-deficiency did not affect oxalate homeostasis, thereby excluding differences in intestinal oxalate handling to explain the observed phenotype. Thus, progressive renal failure in oxalate nephropathy results primarily from NALP3-mediated inflammation. PMID:23739234

Net Intestinal Transport of Oxalate Reflects Passive Absorption and SLC26A6-mediated Secretion

PubMed Central

Knauf, Felix; Ko, Narae; Jiang, Zhirong; Robertson, William G.; Van Itallie, Christina M.; Anderson, James M.

2011-01-01

Mice lacking the oxalate transporter SLC26A6 develop hyperoxalemia, hyperoxaluria, and calcium-oxalate stones as a result of a defect in intestinal oxalate secretion, but what accounts for the absorptive oxalate flux remains unknown. We measured transepithelial absorption of [14C]oxalate simultaneously with the flux of [3H]mannitol, a marker of the paracellular pathway, across intestine from wild-type and Slc26a6-null mice. We used the anion transport inhibitor DIDS to investigate other members of the SLC26 family that may mediate transcellular oxalate absorption. Absorptive flux of oxalate in duodenum was similar to mannitol, insensitive to DIDS, and nonsaturable, indicating that it is predominantly passive and paracellular. In contrast, in wild-type mice, secretory flux of oxalate in duodenum exceeded that of mannitol, was sensitive to DIDS, and saturable, indicating transcellular secretion of oxalate. In Slc26a6-null mice, secretory flux of oxalate was similar to mannitol, and no net flux of oxalate occurred. Absorptive fluxes of both oxalate and mannitol varied in parallel in different segments of small and large intestine. In epithelial cell lines, modulation of the charge selectivity of the claudin-based pore pathway did not affect oxalate permeability, but knockdown of the tight-junction protein ZO-1 enhanced permeability to oxalate and mannitol in parallel. Moreover, formation of soluble complexes with cations did not affect oxalate absorption. In conclusion, absorptive oxalate flux occurs through the paracellular “leak” pathway, and net absorption of dietary oxalate depends on the relative balance between absorption and SLC26A6-dependent transcellular secretion. PMID:22021714

The comparability of oxalate excretion and oxalate:creatinine ratio in the investigation of primary hyperoxaluria: review of data from a referral centre.

PubMed

Clifford-Mobley, Oliver; Tims, Christopher; Rumsby, Gill

2015-01-01

Urine oxalate measurement is an important investigation in the evaluation of renal stone disease. Primary hyperoxaluria (PH) is a rare inherited metabolic disease characterised by persistently elevated urine oxalate, but the diagnosis may be missed in adults until renal failure has developed. Urine oxalate results were reviewed to compare oxalate:creatinine ratio and oxalate excretion, and to estimate the potential numbers of undiagnosed PH. Urine oxalate results from August 2011 to April 2013 were reviewed. Oxalate excretion and oxalate:creatinine ratio were evaluated for 24 h collections and ratio alone for spot urine samples. Oxalate:creatinine ratio and oxalate excretion were moderately correlated (R=0.63) in 24-h urine collections from patients aged 18 years and above. Sex-related differences were found requiring implementation of male and female reference ranges for oxalate:creatinine ratio. Of samples with both ratio and excretion above the reference range, 7% came from patients with confirmed PH. There were 24 patients with grossly elevated urine oxalate who had not been evaluated for PH. Oxalate:creatinine ratio and oxalate excretion were discordant in many patients, which is likely to be a result of intra-individual variation in creatinine output and imprecision in the collection itself. Some PH patients had urine oxalate within the reference range on occasion, and therefore it is not possible to exclude PH on the finding of a single normal result. A significant number of individuals had urine oxalate results well above the reference range who potentially have undiagnosed PH and are consequently at risk of renal failure. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Oxalate quantification in hemodialysate to assess dialysis adequacy for primary hyperoxaluria

PubMed Central

Tang, Xiaojing; Voskoboev, Nikolay V.; Wannarka, Stacie L.; Olson, Julie B.; Milliner, Dawn S.; Lieske, John C.

2015-01-01

Background Patients with primary hyperoxaluria (PH) overproduce oxalate which is eliminated via the kidneys. If end stage kidney disease develops they are at high risk for systemic oxalosis, unless adequate oxalate is removed during hemodialysis to equal or exceed ongoing oxalate production. The purpose of this study was to validate a method to measure oxalate removal in this unique group of dialysis patients. Methods Fourteen stable patients with a confirmed diagnosis of PH on hemodialysis were included in the study. Oxalate was measured serially in hemodialysate and plasma samples in order to calculate rates of oxalate removal. Hemodialysis regimens were adjusted according to a given patient's historical oxalate production, amount of oxalate removal at dialysis, residual renal clearance of oxalate, and plasma oxalate levels. Results After a typical session of hemodialysis, plasma oxalate was reduced by 78.4±7.7%. Eight patients performed hemodialysis 6 times a week, two patients 5 times a week and three patients 3 times a week. Combined oxalate removal by hemodialysis and the kidneys was sufficient to match or exceed endogenous oxalate production. After a median period of 9 months, pre-dialysis plasma oxalate was significantly lower than initially (75.1±33.4 mmol/L vs. 54.8±46.6 mmol/L, P=0.02). Conclusion This methodology can be used to individualize the dialysis prescription of PH patients to prevent oxalosis during the time they are maintained on hemodialysis, and to reduce risk of oxalate injury to a transplanted kidney. PMID:24776840

Influence of a low- and a high-oxalate vegetarian diet on intestinal oxalate absorption and urinary excretion.

PubMed

Thomas, E; von Unruh, G E; Hesse, A

2008-09-01

To compare quantitatively the effect of a low- and a high-oxalate vegetarian diet on intestinal oxalate absorption and urinary excretion. Eight healthy volunteers (three men and five women, mean age 28.6+/-6.3) were studied. Each volunteer performed the [(13)C(2)]oxalate absorption test thrice on a low-oxalate mixed diet, thrice on a low-oxalate vegetarian diet and thrice on a high-oxalate vegetarian diet. For each test, the volunteers had to adhere to an identical diet and collect their 24-h urines. In the morning of the second day, a capsule containing [(13)C(2)]oxalate was ingested. On the low-oxalate vegetarian diet, mean intestinal oxalate absorption and urinary oxalate excretion increased significantly to 15.8+/-2.9% (P=0.012) and 0.414+/-0.126 mmol/day (P=0.012), compared to the mixed diet. On the high-oxalate vegetarian diet, oxalate absorption (12.5+/-4.6%, P=0.161) and urinary excretion (0.340+/-0.077 mmol/day, P=0.093) did not change significantly, compared to the mixed diet. A vegetarian diet can only be recommended for calcium oxalate stone patients, if the diet (1) contains the recommended amounts of divalent cations such as calcium and its timing of ingestion to a meal rich in oxalate is considered and (2) excludes foodstuffs with a high content of nutritional factors, such as phytic acid, which are able to chelate calcium.

The antidepressant effects of running and escitalopram are associated with levels of hippocampal NPY and Y1 receptor but not cell proliferation in a rat model of depression.

PubMed

Bjørnebekk, Astrid; Mathé, Aleksander A; Brené, Stefan

2010-07-01

One hypothesis of depression is that it is caused by reduced neuronal plasticity including hippocampal neurogenesis. In this study, we compared the effects of three long-term antidepressant treatments: escitalopram, voluntary running, and their combination on hippocampal cell proliferation, NPY and the NPY-Y1 receptor mRNAs, targets assumed to be important for hippocampal plasticity and mood disorders. An animal model of depression, the Flinders Sensitive Line (FSL) rat, was used and female rats were chosen because the majority of the depressed population is females. We investigated if these treatments were correlated to immobility, swimming, and climbing behaviors, which are associated with an overall, serotonergic-like and noradrenergic-like antidepressant response, in the Porsolt swim test (PST). Interestingly, while escitalopram, running and their combination increased the number of hippocampal BrdU immunoreactive cells, the antidepressant-like effect was only detected in the running group and the group with access both to running wheel and escitalopram. Hippocampal NPY mRNA and the NPY-Y1 receptor mRNA were elevated by running and the combined treatment. Moreover, correlations were detected between NPY mRNA levels and climbing and cell proliferation and NPY-Y1 receptor mRNA levels and swimming. Our results suggest that increased cell proliferation is not necessarily associated with an antidepressant effect. However, treatments that were associated with an antidepressant-like effect did regulate hippocampal levels of mRNAs encoding NPY and/or the NPY-Y1 receptor and support the notion that NPY can stimulate cell proliferation and induce an antidepressant-like response. Copyright 2009 Wiley-Liss, Inc.

Short-term effects of escitalopram on regional brain function in first-episode drug-naive patients with major depressive disorder assessed by resting-state functional magnetic resonance imaging.

PubMed

Wang, L; Li, K; Zhang, Q; Zeng, Y; Dai, W; Su, Y; Wang, G; Tan, Y; Jin, Z; Yu, X; Si, T

2014-05-01

Most knowledge regarding the effects of antidepressant drugs is at the receptor level, distal from the nervous system effects that mediate their clinical efficacy. Using functional magnetic resonance imaging (fMRI), this study investigated the effects of escitalopram, a selective serotonin reuptake inhibitor (SSRI), on resting-state brain function in patients with major depressive disorder (MDD). Fourteen first-episode drug-naive MDD patients completed two fMRI scans before and after 8 weeks of escitalopram therapy. Scans were also acquired in 14 matched healthy subjects. Data were analyzed using the regional homogeneity (ReHo) approach. Compared to controls, MDD patients before treatment demonstrated decreased ReHo in the frontal (right superior frontal gyrus), temporal (left middle and right inferior temporal gyri), parietal (right precuneus) and occipital (left superior occipital gyrus and right cuneus) cortices, and increased ReHo in the left dorsal medial prefrontal gyrus and left anterior lobe of the cerebellum. Compared to the unmedicated state, ReHo in the patients after treatment was decreased in the left dorsal medial prefrontal gyrus, the right insula and the bilateral thalamus, and increased in the right superior frontal gyrus. Compared to controls, patients after treatment displayed a ReHo decrease in the right precuneus and a ReHo increase in the left anterior lobe of the cerebellum. Successful treatment with escitalopram may be associated with modulation of resting-state brain activity in regions within the fronto-limbic circuit. This study provides new insight into the effects of antidepressants on functional brain systems in MDD.

Changed Synaptic Plasticity in Neural Circuits of Depressive-Like and Escitalopram-Treated Rats

PubMed Central

Li, Xiao-Li; Yuan, Yong-Gui; Xu, Hua; Wu, Di; Gong, Wei-Gang; Geng, Lei-Yu; Wu, Fang-Fang; Tang, Hao; Xu, Lin

2015-01-01

Background: Although progress has been made in the detection and characterization of neural plasticity in depression, it has not been fully understood in individual synaptic changes in the neural circuits under chronic stress and antidepressant treatment. Methods: Using electron microscopy and Western-blot analyses, the present study quantitatively examined the changes in the Gray’s Type I synaptic ultrastructures and the expression of synapse-associated proteins in the key brain regions of rats’ depressive-related neural circuit after chronic unpredicted mild stress and/or escitalopram administration. Meanwhile, their depressive behaviors were also determined by several tests. Results: The Type I synapses underwent considerable remodeling after chronic unpredicted mild stress, which resulted in the changed width of the synaptic cleft, length of the active zone, postsynaptic density thickness, and/or synaptic curvature in the subregions of medial prefrontal cortex and hippocampus, as well as the basolateral amygdaloid nucleus of the amygdala, accompanied by changed expression of several synapse-associated proteins. Chronic escitalopram administration significantly changed the above alternations in the chronic unpredicted mild stress rats but had little effect on normal controls. Also, there was a positive correlation between the locomotor activity and the maximal synaptic postsynaptic density thickness in the stratum radiatum of the Cornu Ammonis 1 region and a negative correlation between the sucrose preference and the length of the active zone in the basolateral amygdaloid nucleus region in chronic unpredicted mild stress rats. Conclusion: These findings strongly indicate that chronic stress and escitalopram can alter synaptic plasticity in the neural circuits, and the remodeled synaptic ultrastructure was correlated with the rats’ depressive behaviors, suggesting a therapeutic target for further exploration. PMID:25899067

Risk of Ventricular Arrhythmia with Citalopram and Escitalopram: A Population-Based Study.

PubMed

Qirjazi, Elena; McArthur, Eric; Nash, Danielle M; Dixon, Stephanie N; Weir, Matthew A; Vasudev, Akshya; Jandoc, Racquel; Gula, Lorne J; Oliver, Matthew J; Wald, Ron; Garg, Amit X

2016-01-01

The risk of ventricular arrhythmia with citalopram and escitalopram is controversial. In this study we investigated the association between these two drugs and the risk of ventricular arrhythmia. We conducted a population-based retrospective cohort study of older adults (mean age 76 years) from 2002 to 2012 in Ontario, Canada, newly prescribed citalopram (n = 137 701) or escitalopram (n = 38 436), compared to those prescribed referent antidepressants sertraline or paroxetine (n = 96 620). After inverse probability of treatment weighting using a propensity score, the baseline characteristics of the comparison groups were similar. The primary outcome was a hospital encounter with ventricular arrhythmia within 90 days of a new prescription, assessed using hospital diagnostic codes. The secondary outcome was all-cause mortality within 90 days. Citalopram was associated with a higher risk of a hospital encounter with ventricular arrhythmia compared with referent antidepressants (0.06% vs. 0.04%, relative risk [RR] 1.53, 95% confidence intervals [CI]1.03 to 2.29), and a higher risk of mortality (3.49% vs. 3.12%, RR 1.12, 95% CI 1.06 to 1.18). Escitalopram was not associated with a higher risk of ventricular arrhythmia compared with the referent antidepressants (0.03% vs. 0.04%, RR 0.84, 95% CI 0.42 to 1.68), but was associated with a higher risk of mortality (2.86% vs. 2.63%, RR 1.09, 95% CI 1.01 to 1.18). Among older adults, initiation of citalopram compared to two referent antidepressants was associated with a small but statistically significant increase in the 90-day risk of a hospital encounter for ventricular arrhythmia.

Serotonin transporter occupancy by escitalopram and citalopram in the non-human primate brain: a [(11)C]MADAM PET study.

PubMed

Finnema, Sjoerd J; Halldin, Christer; Bang-Andersen, Benny; Bundgaard, Christoffer; Farde, Lars

2015-11-01

A number of serotonin receptor positron emission tomography (PET) radioligands have been shown to be sensitive to changes in extracellular serotonin concentration, in a generalization of the well-known dopamine competition model. High doses of selective serotonin reuptake inhibitors (SSRIs) decrease serotonin receptor availability in monkey brain, consistent with increased serotonin concentrations. However, two recent studies on healthy human subjects, using a single, lower and clinically relevant SSRI dose, showed increased cortical serotonin receptor radioligand binding, suggesting potential decreases in serotonin concentration in projection regions when initiating treatment. The cross-species differential SSRI effect may be partly explained by serotonin transporter (SERT) occupancy in monkey brain being higher than is clinically relevant. We here determine SERT occupancy after single doses of escitalopram or citalopram by conducting PET measurements with [(11)C]MADAM in monkeys. Relationships between dose, plasma concentration and SERT occupancy were estimated by one-site binding analyses. Binding affinity was expressed as dose (ID50) or plasma concentration (K i) where 50 % SERT occupancy was achieved. Estimated ID50 and K i values were 0.020 mg/kg and 9.6 nmol/L for escitalopram and 0.059 mg/kg and 9.7 nmol/L for citalopram, respectively. Obtained K i values are comparable to values reported in humans. Escitalopram or citalopram doses nearly saturated SERT in previous monkey studies which examined serotonin sensitivity of receptor radioligands. PET-measured cross-species differential effects of SSRI on cortical serotonin concentration may thus be related to SSRI dose. Future monkey studies using SSRI doses inducing clinically relevant SERT occupancy may further illuminate the delayed onset of SSRI therapeutic effects.

Prenatal stress, regardless of concurrent escitalopram treatment, alters behavior and amygdala gene expression of adolescent female rats

PubMed Central

Ehrlich, David E.; Neigh, Gretchen N.; Bourke, Chase H.; Nemeth, Christina L.; Hazra, Rimi; Ryan, Steven J.; Rowson, Sydney; Jairam, Nesha; Sholar, Courtney; Rainnie, Donald G.; Stowe, Zachary N.; Owens, Michael J.

2015-01-01

Depression during pregnancy has been linked to in utero stress and is associated with long-lasting symptoms in offspring, including anxiety, helplessness, attentional deficits, and social withdrawal. Depression is diagnosed in 10-20% of expectant mothers, but the impact of antidepressant treatment on offspring development is not well documented, particularly for females. Here, we used a prenatal stress model of maternal depression to test the hypothesis that in utero antidepressant treatment could mitigate the effects of prenatal stress. We also investigated the effects of prenatal stress and antidepressant treatment on gene expression related to GABAergic and serotonergic neurotransmission in the amygdala, which may underlie behavioral effects of prenatal stress. Nulliparous female rats were implanted with osmotic minipumps delivering clinically-relevant concentrations of escitalopram and mated. Pregnant dams were exposed to 12 days of mixed-modality stressors, and offspring were behaviorally assessed in adolescence (postnatal day 28) and adulthood (beyond day 90) to determine the extent of behavioral change. We found that in utero stress exposure, regardless of escitalopram treatment, increased anxiety-like behavior in adolescent females and profoundly influenced amygdala expression of the chloride transporters KCC2 and NKCC1, which regulate GABAergic function. In contrast, prenatal escitalopram exposure alone elevated amygdala expression of 5-HT1A receptors. In adulthood, anxiety-like behavior returned to baseline and gene expression effects in the amygdala abated, whereas deficits emerged in novel object recognition for rats exposed to stress during gestation. These findings suggest prenatal stress causes age-dependent deficits in anxiety-like behavior and amygdala function in female offspring, regardless of antidepressant exposure. PMID:26032436

Risk of Ventricular Arrhythmia with Citalopram and Escitalopram: A Population-Based Study

PubMed Central

Qirjazi, Elena; McArthur, Eric; Nash, Danielle M.; Dixon, Stephanie N.; Weir, Matthew A.; Vasudev, Akshya; Jandoc, Racquel; Gula, Lorne J.; Oliver, Matthew J.; Wald, Ron; Garg, Amit X.

2016-01-01

Background The risk of ventricular arrhythmia with citalopram and escitalopram is controversial. In this study we investigated the association between these two drugs and the risk of ventricular arrhythmia. Methods We conducted a population-based retrospective cohort study of older adults (mean age 76 years) from 2002 to 2012 in Ontario, Canada, newly prescribed citalopram (n = 137 701) or escitalopram (n = 38 436), compared to those prescribed referent antidepressants sertraline or paroxetine (n = 96 620). After inverse probability of treatment weighting using a propensity score, the baseline characteristics of the comparison groups were similar. The primary outcome was a hospital encounter with ventricular arrhythmia within 90 days of a new prescription, assessed using hospital diagnostic codes. The secondary outcome was all-cause mortality within 90 days. Results Citalopram was associated with a higher risk of a hospital encounter with ventricular arrhythmia compared with referent antidepressants (0.06% vs. 0.04%, relative risk [RR] 1.53, 95% confidence intervals [CI]1.03 to 2.29), and a higher risk of mortality (3.49% vs. 3.12%, RR 1.12, 95% CI 1.06 to 1.18). Escitalopram was not associated with a higher risk of ventricular arrhythmia compared with the referent antidepressants (0.03% vs. 0.04%, RR 0.84, 95% CI 0.42 to 1.68), but was associated with a higher risk of mortality (2.86% vs. 2.63%, RR 1.09, 95% CI 1.01 to 1.18). Conclusion Among older adults, initiation of citalopram compared to two referent antidepressants was associated with a small but statistically significant increase in the 90-day risk of a hospital encounter for ventricular arrhythmia. PMID:27513855

Using a partner's facial emotion to elucidate social dominance motivation induced by an SSRI.

PubMed

Tse, Wai S; Chow, H; Wing, Y K; Bond, Alyson J

2014-10-01

Previous studies independently showed that acute treatment with a selective serotonin reuptake inhibitor (SSRI) enhanced happy face recognition, and dominance behaviors which might reflect enhancement of reward sensitivity. The present study aimed to determine whether such a mechanism would be related to social resource acquisition induced by an SSRI. Forty healthy subjects were recruited for the experiment. A randomized, double-blind, placebo-controlled crossover nested within confederate type (happy, fearful, or sad) trial of a single-dose of 10mg escitalopram versus placebo was conducted with a two-week washout period. In each of the treatment groups, the subjects interacted socially with one of the three types of confederate in a waiting room for 3-minute. Then, they went to an individual laboratory and were led to believe that they played the Mixed-motive game with the confederate. The game measures punitive/cooperative behaviors by how participants allocate higher/lower game scores to the confederate and communicate cooperation/ingratiation/helplessness/sadness/blaming/extrapunitive, messages to the confederate. Significant treatment-by-confederate type interactions were observed through game score distributions and ingratiation messages to the confederate and attentive eye gaze. In the happy confederate condition, escitalopram increased ingratiation messages and lowered points awarded to the confederate. In the fearful confederate condition, escitalopram increased ingratiation messages and reduced time spent looking away from the confederate. No changes in these measures were found in the sad confederate condition. Therefore acute escitalopram treatment enhances reward sensitivity to the facial emotions of social partners which in turn increases social resource acquisition and social dominance towards happy but not fearful social partners. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

Chronic treatment with caffeine and its withdrawal modify the antidepressant-like activity of selective serotonin reuptake inhibitors in the forced swim and tail suspension tests in mice. Effects on Comt, Slc6a15 and Adora1 gene expression.

PubMed

Szopa, Aleksandra; Doboszewska, Urszula; Herbet, Mariola; Wośko, Sylwia; Wyska, Elżbieta; Świąder, Katarzyna; Serefko, Anna; Korga, Agnieszka; Wlaź, Aleksandra; Wróbel, Andrzej; Ostrowska, Marta; Terlecka, Joanna; Kanadys, Adam; Poleszak, Ewa; Dudka, Jarosław; Wlaź, Piotr

2017-12-15

Recent preclinical and clinical data suggest that low dose of caffeine enhances the effects of common antidepressants. Here we investigated the effects of chronic administration of caffeine (5mg/kg, twice daily for 14days) and its withdrawal on day 15th on the activity of per se ineffective doses of fluoxetine (5mg/kg) and escitalopram (2mg/kg) given on day 15th. We found decreased immobility time in the forced swim and tail suspension tests in mice in which caffeine was administered simultaneously with antidepressants on day 15th following a 14-day caffeine treatment and no alterations in the spontaneous locomotor activity. A decrease in the level of escitalopram and an increase in the level of caffeine in serum were observed after concomitant administration of these compounds, while the joint administration of caffeine and fluoxetine was not associated with changes in their levels in serum or brain. Caffeine withdrawal caused a decrease in Adora1 mRNA level in the cerebral cortex (Cx). Administration of escitalopram or fluoxetine followed by caffeine withdrawal caused an increase in this gene expression, whereas administration of escitalopram, but not fluoxetine, on day 15th together with caffeine caused a decrease in Adora1 mRNA level in the Cx. Furthermore, antidepressant-like activity observed after joint administration of the tested drugs with caffeine was associated with decreased Slc6a15 mRNA level in the Cx. The results show that withdrawal of caffeine after its chronic intake may change activity of antidepressants with concomitant alterations within monoamine, adenosine and glutamate systems. Copyright © 2017 Elsevier Inc. All rights reserved.

A Randomized, Controlled, Pilot Study of Acamprosate Added to Escitalopram in Adults With Major Depressive Disorder and Alcohol Use Disorder

PubMed Central

Witte, Janet; Bentley, Kate; Eden Evins, Anne; Clain, Alisabet J.; Baer, Lee; Pedrelli, Paola; Fava, Maurizio; Mischoulon, David

2013-01-01

We sought to examine the efficacy and safety of acamprosate augmentation of escitalopram in patients with concurrent major depressive disorder (MDD) and alcohol use disorders. Twenty-three adults (43% female; mean ± SD age, 46 ± 14 years) were enrolled and received 12 weeks of treatment with psychosocial support; escitalopram, 10 to 30 mg/d; and either acamprosate, 2000 mg/d (n = 12), or identical placebo (n = 11). Outcomes included change in clinician ratings of depressive symptoms, MDD response and remission rates, changes in frequency and intensity of alcohol use, retention rates, and adverse events. Twelve subjects (acamprosate, n = 7; placebo, n = 5) completed the study. There was significant mean reduction in ratings of depressive symptoms from baseline in both treatment arms (P < 0.05), with no significant difference between the groups. Those in the acamprosate group had a 50% MDD response rate and a 42% remission rate, whereas those in the placebo arm had a 36% response and remission rate (not significant). Those assigned to acamprosate had significant reduction in number of drinks per week and drinks per month during the trial, whereas those assigned to placebo demonstrated no significant change in any alcohol use parameter, but the between-group difference was not significant. There were no significant associations between change in depressive symptoms and change in alcohol use. Attrition rates did not differ significantly between the 2 arms. Acamprosate added to escitalopram in adults with MDD and alcohol use disorders was associated with reduction in the frequency of alcohol use. The present study was not powered to detect superiority versus placebo. Further study in a larger sample is warranted. PMID:23131884

The Roles and Mechanisms of Intestinal Oxalate Transport in Oxalate Homeostasis

PubMed Central

Hatch, Marguerite; Freel, Robert W.

2008-01-01

The mammalian intestine has an important role in the dynamics of oxalate exchange and thereby is significant in the etiology of calcium oxalate nephrolithiasis. Here we review some of the phenomenological observations that have led to the conclusion that anion exchangers (antiporters) are important mediators of secondarily active, net oxalate transport along the intestine (both absorptive and secretory). Understanding the mechanisms of transepithelial oxalate transport has been radically advanced in recent years by the identification of the SLC26 family of anion transporters which has facilitated the identification of specific proteins mediating individual apical or basolateral oxalate transport pathways. Moreover, identification of specific exchangers has underscored their relative importance to oxalate homeostasis as revealed by using knockout mouse models and facilitated studies of oxalate transport regulation in heterologous expression systems. Finally, the significance of oxalate degrading bacteria to oxalate homeostasis is considered from basic and applied perspectives. PMID:18359395

Degradation of oxalate in rats implanted with immobilized oxalate oxidase.

PubMed

Raghavan, K G; Tarachand, U

1986-01-20

Accumulation of oxalate leads to hyperoxaluria and calcium oxalate nephrolithiasis in man. Since oxalate is a metabolic end product in mammals, the feasibility of its enzymic degradation has been tested in vivo in rats by administering exogenous oxalate oxidase. Oxalate oxidase, isolated from banana fruit peels, in its native form was found to be non-active at the physiological pH of the recipient animal. However, its functional viability in the recipient animal was ensured by its prior binding with ethylenemaleic anhydride, thus shifting its pH activity curve towards the alkaline range. Rats implanted with dialysis membrane capsules containing such immobilized oxalate oxidase in their peritoneal cavities effectively metabolized intraperitoneally injected [14C]oxalate as well as its precursor [14C]glyoxalate. The implantation of capsules containing coentrapped multienzyme preparations of oxalate oxidase, catalase and peroxidase led to a further degradation of administered [14C]oxalate in rats.

Oxalate content of cereals and cereal products.

PubMed

Siener, Roswitha; Hönow, Ruth; Voss, Susanne; Seidler, Ana; Hesse, Albrecht

2006-04-19

Detailed knowledge of food oxalate content is of essential importance for dietary treatment of recurrent calcium oxalate urolithiasis. Dietary oxalate can contribute considerably to the amount of urinary oxalate excretion. Because cereal foods play an important role in daily nutrition, the soluble and total oxalate contents of various types of cereal grains, milling products, bread, pastries, and pasta were analyzed using an HPLC-enzyme-reactor method. A high total oxalate content (>50 mg/100 g) was found in whole grain wheat species Triticum durum (76.6 mg/100 g), Triticum sativum (71.2 mg/100 g), and Triticum aestivum (53.3 mg/100 g). Total oxalate content was comparably high in whole grain products of T. aestivum, that is, wheat flakes and flour, as well as in whole grain products of T. durum, that is, couscous, bulgur, and pasta. The highest oxalate content was demonstrated for wheat bran (457.4 mg/100 g). The higher oxalate content in whole grain than in refined grain cereals suggests that oxalic acid is primarily located in the outer layers of cereal grains. Cereals and cereal products contribute to the daily oxalate intake to a considerable extent. Vegetarian diets may contain high amounts of oxalate when whole grain wheat and wheat products are ingested. Recommendations for prevention of recurrence of calcium oxalate stone disease have to take into account the oxalate content of these foodstuffs.

Oxalates in oca (New Zealand yam) (Oxalis tuberosa Mol.).

PubMed

Ross, A B; Savage, G P; Martin, R J; Vanhanen, L

1999-12-01

Oca (Oxalis tuberosa Mol.) or New Zealand yam, in common with other members of this genus, contains oxalate, an antinutritive factor. Twelve South American and two New Zealand cultivars of oca were analyzed for total and soluble oxalate contents of the tubers. The range of total oxalate levels was 92-221 mg/100 g of fresh weight. Levels of soluble and total oxalate extracted from the tubers were not significantly different, suggesting that no calcium oxalate is formed in the tubers. The oxalate concentrations obtained in this study for oca suggest that previously reported values are too low and that oca is a moderately high oxalate-containing food. This is the first report of a tuber crop containing moderate to high levels of soluble oxalates in the tubers and no insoluble oxalates.

Evidence for net renal tubule oxalate secretion in patients with calcium kidney stones

PubMed Central

Zisman, Anna L.; Asplin, John R.; Worcester, Elaine M.; Coe, Fredric L.

2011-01-01

Little is known about the renal handling of oxalate in patients with idiopathic hypercalciuria (IH). To explore the role of tubular oxalate handling in IH and to evaluate whether differences exist between IH and normal controls, we studied 19 IH subjects, 8 normal subjects, and 2 bariatric stone formers (BSF) during a 1-day General Clinical Research Center protocol utilizing a low-oxalate diet. Urine and blood samples were collected at 30- to 60-min intervals while subjects were fasting and after they ate three meals providing known amounts of calcium, phosphorus, sodium, protein, oxalate, and calories. Plasma oxalate concentrations and oxalate-filtered loads were similar between patients (includes IH and BSF) and controls in both the fasting and fed states. Urinary oxalate excretion was significantly higher in patients vs. controls regardless of feeding state. Fractional excretion of oxalate (FEOx) was >1, suggesting tubular secretion of oxalate, in 6 of 19 IH and both BSF, compared with none of the controls (P < 0.00001). Adjusted for water extraction along the nephron, urine oxalate rose more rapidly among patients than normal subjects with increases in plasma oxalate. Our findings identify tubular secretion of oxalate as a key mediator of hyperoxaluria in calcium stone formers, potentially as a means of maintaining plasma oxalate in a tight range. PMID:21123489

Oxalate Content of the Herb Good-King-Henry, Blitum Bonus-Henricus

PubMed Central

Li, Wanying; Savage, Geoffrey P.

2015-01-01

The total, soluble and insoluble oxalate contents of the leaves, stems and buds of Good-King-Henry (Blitum Bonus-Henricus) were extracted and measured using HPLC chromatography. The large, mature leaves contained 42% more total oxalate than in the small leaves and the soluble oxalate content of the large leaves was 33% higher than the smaller leaves. Cooking the mixed leaves, stems and buds in boiling water for two minutes significantly (p < 0.05) reduced the total oxalate when compared to the raw plant parts. Pesto sauce made from mixed leaves contained 257 mg total oxalate/100 g fresh weight; this was largely made up of insoluble oxalates (85% of the total oxalate content). Soup made from mixed leaves contained lower levels of total oxalates (44.26 ± 0.49 mg total oxalate/100 g fresh weight) and insoluble oxalate made up 49% of the oxalate contents. The levels of oxalates in the Good-King-Henry leaves were high, suggesting that the leaves should be consumed occasionally as a delicacy because of their unique taste rather than as a significant part of the diet. However, the products made from Good-King-Henry leaves indicated that larger amounts could be consumed as the oxalate levels were reduced by dilution and processing. PMID:28231194

[Clinical study on depression differentiated as yang deficiency treated with the combined therapy of ginger-isolated moxibustion and western medicine].

PubMed

Xie, Yanying; Liu, Liangsheng; Xie, Jiajiang

2016-12-12

To compare the differences in the clinical efficacy on depression differentiated as yang deficiency between the combined therapy of ginger-isolated moxibustion and escitalopram and the simple application escitalopram. Eighty patients of depression differentiated as yang deficiency were randomized into an observation group and a control group, 40 cases in each one. In the control group, escitalopram was prescribed for oral administration, 10 mg a day, after each breakfast. In the observation group, on the basis of the treatment as the control group, the ginger-isolated moxibustion was supplemented at Dazhui (GV 14) and bilateral back- shu points of five zang organs[Xinshu (BL 15), Ganshu (BL 18), Pishu (BL 20), Feishu (BL 13) and Shenshu (BL 23)]. Moxibustion was used 5 times a week. Twenty times of moxibustion were taken as one session and totally 3 sessions were required (totally 84 days). After 3 sessions of treatment, the concentration of serum 5-hydroxytryptamine (5-HT) before and after treatment and clinical efficacy were observed in the two groups. After 3 sessions of treatment, escitalopram was taken continuously, 10 mg a day for 9 months in the two groups and the recurrent rate was observed in a half year after discontinuity of medication in the two groups. The total effective rate was 97.5% (39/40) in the observation group and was 92.5% (37/40) in the control group. The total effective rate was similar between the two groups (both P >0.05). The curative and remarkably effective rate was 82.5% (33/40) in the observation group, better than 62.5% (25/40) in the control group ( P <0.05). The serum 5-HT after treatment was increased as compared with that before treatment in the patients of the two groups (both P <0.05), but the diffe-rence was not significant statistically between the two groups ( P >0.05). The recurrent rate of depression was 7.7% (3/39) in the observation group, lower than 27.0% (10/37) in the control group ( P <0.05). The combined therapy of ginger-isolated moxibustion and escitalopram achieves the better curative and remarkably effective rate as compared with the simple western medicine and it significantly reduces the recurrence of depression.

Oxalobacter formigenes Colonization and Oxalate Dynamics in a Mouse Model

PubMed Central

Li, Xingsheng; Ellis, Melissa L.

2015-01-01

Animal and human studies have provided compelling evidence that colonization of the intestine with Oxalobacter formigenes reduces urinary oxalate excretion and lowers the risk of forming calcium oxalate kidney stones. The mechanism providing protection appears to be related to the unique ability of O. formigenes to rely on oxalate as a major source of carbon and energy for growth. However, much is not known about the factors that influence colonization and host-bacterium interactions. We have colonized mice with O. formigenes OxCC13 and systematically investigated the impacts of diets with different levels of calcium and oxalate on O. formigenes intestinal densities and urinary and intestinal oxalate levels. Measurement of intestinal oxalate levels in mice colonized or not colonized with O. formigenes demonstrated the highly efficient degradation of soluble oxalate by O. formigenes relative to other microbiota. The ratio of calcium to oxalate in diets was important in determining colonization densities and conditions where urinary oxalate and fecal oxalate excretion were modified, and the results were consistent with those from studies we have performed with colonized and noncolonized humans. The use of low-oxalate purified diets showed that 80% of animals retained O. formigenes colonization after a 1-week dietary oxalate deprivation. Animals not colonized with O. formigenes excreted two times more oxalate in feces than they had ingested. This nondietary source of oxalate may play an important role in the survival of O. formigenes during periods of dietary oxalate deprivation. These studies suggest that the mouse will be a useful model to further characterize interactions between O. formigenes and the host and factors that impact colonization. PMID:25979889

Oxalate, inflammasome, and progression of kidney disease

PubMed Central

Ermer, Theresa; Eckardt, Kai-Uwe; Aronson, Peter S.; Knauf, Felix

2016-01-01

Purpose of review Oxalate is an end product of metabolism excreted via the kidney. Excess urinary oxalate, whether from primary or enteric hyperoxaluria, can lead to oxalate deposition in the kidney. Oxalate crystals are associated with renal inflammation, fibrosis and progressive renal failure. It has long been known that as glomerular filtration rate (GFR) becomes reduced in chronic kidney disease (CKD), there is striking elevation of plasma oxalate. Taken together, these findings raise the possibility that elevation of plasma oxalate in CKD may promote renal inflammation and more rapid progression of CKD independent of primary etiology. Recent findings The inflammasome has recently been identified to play a critical role in oxalate-induced renal inflammation. Oxalate crystals have been shown to activate the nucleotide-binding domain, leucine-rich repeat inflammasome 3 (also known as NALP3, NLRP3 or cryopyrin), resulting in release of Interleukin-1β and macrophage infiltration. Deletion of inflammasome proteins in mice protects from oxalate-induced renal inflammation and progressive renal failure. Summary The findings reviewed in this article expand our understanding of the relevance of elevated plasma oxalate levels leading to inflammasome activation. We propose that inhibiting oxalate-induced inflammasome activation, or lowering plasma oxalate, may prevent or mitigate progressive renal damage in CKD, and warrants clinical trials. PMID:27191349

Calcium oxalate contribution to calcium cycling in forests of contrasting nutrient status

USGS Publications Warehouse

Dauer, Jenny M.; Perakis, Steven S.

2014-01-01

Calcium oxalate (Ca oxalate) is an insoluble biomineral that forms in plants and fungi, and occurs in soils across many types of ecosystems. Assessing how Ca oxalate may shape ecosystem Ca cycling requires information on the distribution of Ca oxalate among plant biomass, detritus, and mineral soil, and how it varies with ecosystem Ca status. We compared two Douglas-fir forests of contrasting ecosystem Ca availability, and found that Ca oxalate was partitioned similarly among plant biomass, detritus and mineral soil major ecosystem compartments at both sites, and total pools of Ca oxalate were greater in the high-Ca forest. However, the proportional importance of Ca oxalate was greater in the low-Ca than high-Ca forest (18% versus 4% of actively cycling ecosystem Ca, respectively). And calcium oxalate in mineral soil, which is of particular interest as a potential long-term Ca reservoir, was a larger portion of total available Ca (exchangeable Ca plus Ca oxalate Ca) in the low-Ca site than the high-Ca site (9% versus 1% of available soil Ca, respectively). Calcium oxalate was the dominant form of Ca returned from plants to soil as leaf litterfall at the high-Ca site, yet calcium oxalate disappeared rapidly from decomposing litter (0.28 yr−1 or faster) at both sites. We conclude that accumulation of Ca oxalate in forest ecosystems appears most closely related to overall Ca supply for live biomass pools, and that the accumulation of Ca oxalate in forest floor and mineral soil is limited by rapid microbial degradation of putatively unavailable Ca oxalate.

Oxalate and Sucralose Absorption in Idiopathic Calcium Oxalate Stone Formers

PubMed Central

Knight, John; Jiang, Juquan; Wood, Kyle D.; Holmes, Ross P.; Assimos, Dean G.

2011-01-01

Objectives Oxalate has been hypothesized to undergo absorption in the large and small intestine by both paracellular and transepithelial transport. Sucralose is a chlorinated sugar that is absorbed by paracellular mechanisms. This study's objective was to better understand intestinal oxalate transport by correlating oxalate and sucralose absorption in idiopathic calcium oxalate stone formers. Methods Idiopathic calcium oxalate stone formers were recruited to provide urine specimens on both a self-selected diet and following a meal containing 90 mg of 13C2-oxalate and 5 grams of sucralose, and a stool sample for determination of Oxalobacter formigenes colonization. The 24 hour urine collections were fractionated into the first 6 hours and the subsequent 18 hours. Sucralose and oxalate excretion were measured during these periods and used to estimate absorption. Results A total of 38 subjects were evaluated. The majority of both the 13C2-oxalate and sucralose absorption occurred within the 0-6 hour collection. The 13C2-oxalate and sucralose absorptions were significantly correlated at the 0-6 hour, the 6-24 hour, and the total 24 hour time periods (p<0.04). All five oxalate hyperabsorbers(> 15% absorption) also absorbed significantly more sucralose during the 0-6 hour and whole 24 hour time points (p<0.04). Oxalobacter formigenes colonization did not significantly alter oxalate absorption. Conclusion The results suggest that the majority of oxalate is absorbed in the proximal portion of the gastrointestinal tract and that paracelluar transport is involved. Augmented paracellular transport, as evidenced by increased sucralose absorption, may also influence oxalate absorption. PMID:21676449

Effect of metal complex formation on the potential of organic aerosols as cloud condensation nuclei

NASA Astrophysics Data System (ADS)

Furukawa, T.; Takahashi, Y.

2010-12-01

Secondary organic aerosols (SOA) play a key role on the solar radiation balance in troposphere, since SOA can act as cloud condensation nuclei (CCN) due to its high hygroscopic nature. Oxalic acid is one of the most dominant components of SOA, which has cooling effects of the earth by acting as CCN. However, it is uncertain whether the oxalic acid can exist as free oxalic acid or metal-oxalate complexes in aerosols, even if there is a largedifference in their solubilities into water. Consequently, XAFS measurement was conducted to demonstrate the presence of metal-oxalate complexes. Size fractionated aerosol samples were collected in Tsukuba (located at northeast about 60 km from Tokyo) using a low-volume Andersen-type air sampler. The sampler had eight stages and a back-up filter. The sampling was conducted during winter and summer in 2002. Calcium oxalate was observed in finer particles in each period from Ca K-edge XANES, and its fractions among total Ca were approximately 20%. Similarly,, Zn oxalate was also detected in finer particles from Zn K-edge XANES and EXAFS. The [Zn-oxalate] / [Zn]total ratio in each period clearly increased with the decrease in the particle diameter. This result revealed that Zn-oxalate was formed in the aqueous phase at particle surfaces or in cloud processing. In other words, Zn-oxalate was abundant at the particle surface, resulting from the increase in the [surface]/[bulk] ratio with decreasing particle size. Based on (i) total concentrations of oxalate, Ca, and Zn determined by ion-chromatography and ICP-AES analyses and (ii) Ca- and Zn- oxalate fractions obtained by XAFS, we determined the fraction of metal-oxalate complexes among total oxalate in aerosols. In winter, Ca- and Zn- oxalate fractions reached about 60% of total oxalate in the ranges of 1.1-2.1 μm and 0.65-1.1 μm, while the value was about 60-80% in the same particle size range in summer. On the other hand, Ca- and Zn- oxalates are highly insoluble, showing that the complexes cannot act as CCN. Therefore, the ability of oxalic acid as CCN is needed to be reconsidered, because most of oxalic acid in aerosols exists as metal-oxalate complexes as shown by XAFS spectroscopy in this study.

Plasma oxalic acid and calcium levels in oxalate poisoning

PubMed Central

Zarembski, P. M.; Hodgkinson, A.

1967-01-01

Observations are reported on five cases of suicide or attempted suicide by poisoning with oxalic acid or ethylene glycol. Elevated oxalic acid levels were observed in the plasma, stomach contents, and a number of tissues. Raised oxalic acid levels in plasma were associated with reduced total and ultrafilterable calcium levels. It is suggested that the reduction in plasma total calcium level is due mainly to the deposition of calcium oxalate in the soft tissues, but inhibition of the parathyroid glands may be a contributory factor. Microscopic examination of various tissues indicated that oxalic acid is deposited in the tissues in two forms: (1) crystalline calcium oxalate dihydrate in the kidney and (2) a non-crystalline complex of calcium oxalate and lipid in liver and other tissues. PMID:5602563

Enteric oxalate elimination is induced and oxalate is normalized in a mouse model of primary hyperoxaluria following intestinal colonization with Oxalobacter

PubMed Central

Gjymishka, Altin; Salido, Eduardo C.; Allison, Milton J.; Freel, Robert W.

2011-01-01

Oxalobacter colonization of rat intestine was previously shown to promote enteric oxalate secretion and elimination, leading to significant reductions in urinary oxalate excretion (Hatch et al. Kidney Int 69: 691–698, 2006). The main goal of the present study, using a mouse model of primary hyperoxaluria type 1 (PH1), was to test the hypothesis that colonization of the mouse gut by Oxalobacter formigenes could enhance enteric oxalate secretion and effectively reduce the hyperoxaluria associated with this genetic disease. Wild-type (WT) mice and mice deficient in liver alanine-glyoxylate aminotransferase (Agxt) exhibiting hyperoxalemia and hyperoxaluria were used in these studies. We compared the unidirectional and net fluxes of oxalate across isolated, short-circuited large intestine of artificially colonized and noncolonized mice. In addition, plasma and urinary oxalate was determined. Our results demonstrate that the cecum and distal colon contribute significantly to enteric oxalate excretion in Oxalobacter-colonized Agxt and WT mice. In colonized Agxt mice, urinary oxalate excretion was reduced 50% (to within the normal range observed for WT mice). Moreover, plasma oxalate concentrations in Agxt mice were also normalized (reduced 50%). Colonization of WT mice was also associated with marked (up to 95%) reductions in urinary oxalate excretion. We conclude that segment-specific effects of Oxalobacter on intestinal oxalate transport in the PH1 mouse model are associated with a normalization of plasma oxalate and urinary oxalate excretion in otherwise hyperoxalemic and hyperoxaluric animals. PMID:21163900

Sat1 is dispensable for active oxalate secretion in mouse duodenum

PubMed Central

Ko, Narae; Knauf, Felix; Jiang, Zhirong; Markovich, Daniel

2012-01-01

Mice deficient for the apical membrane oxalate transporter SLC26A6 develop hyperoxalemia, hyperoxaluria, and calcium oxalate stones due to a defect in intestinal oxalate secretion. However, the nature of the basolateral membrane oxalate transport process that operates in series with SLC26A6 to mediate active oxalate secretion in the intestine remains unknown. Sulfate anion transporter-1 (Sat1 or SLC26A1) is a basolateral membrane anion exchanger that mediates intestinal oxalate transport. Moreover, Sat1-deficient mice also have a phenotype of hyperoxalemia, hyperoxaluria, and calcium oxalate stones. We, therefore, tested the role of Sat1 in mouse duodenum, a tissue with Sat1 expression and SLC26A6-dependent oxalate secretion. Although the active secretory flux of oxalate across mouse duodenum was strongly inhibited (>90%) by addition of the disulfonic stilbene DIDS to the basolateral solution, secretion was unaffected by changes in medium concentrations of sulfate and bicarbonate, key substrates for Sat1-mediated anion exchange. Inhibition of intracellular bicarbonate production by acetazolamide and complete removal of bicarbonate from the buffer also produced no change in oxalate secretion. Finally, active oxalate secretion was not reduced in Sat1-null mice. We conclude that a DIDS-sensitive basolateral transporter is involved in mediating oxalate secretion across mouse duodenum, but Sat1 itself is dispensable for this process. PMID:22517357

Oxalate content of some common foods: determination by an enzymatic method.

PubMed

Kasidas, G P; Rose, G A

1980-08-01

A specific enzymatic method was used to determine the oxalate content of some common foods. No preliminary isolation of oxalate was required and recoveries ranging from 95-110 per cent were obtained. Spinach, rhubarb, peanuts, chocolates, parsley and tea were found to contain high levels of oxalate as previously described by others. On the other hand the oxalate content of beetroot was found to be five times as high as previously reported, but coca-cola and beer were almost free from oxalate. Cereals and meat were either low or deficient in oxalate.

Hydroxyproline Metabolism and Oxalate Synthesis in Primary Hyperoxaluria.

PubMed

Fargue, Sonia; Milliner, Dawn S; Knight, John; Olson, Julie B; Lowther, W Todd; Holmes, Ross P

2018-06-01

Background Endogenous oxalate synthesis contributes to calcium oxalate stone disease and is markedly increased in the inherited primary hyperoxaluria (PH) disorders. The incomplete knowledge regarding oxalate synthesis complicates discovery of new treatments. Hydroxyproline (Hyp) metabolism results in the formation of oxalate and glycolate. However, the relative contribution of Hyp metabolism to endogenous oxalate and glycolate synthesis is not known. Methods To define this contribution, we performed primed, continuous, intravenous infusions of the stable isotope [ 15 N, 13 C 5 ]-Hyp in nine healthy subjects and 19 individuals with PH and quantified the levels of urinary 13 C 2 -oxalate and 13 C 2 -glycolate formed using ion chromatography coupled to mass detection. Results The total urinary oxalate-to-creatinine ratio during the infusion was 73.1, 70.8, 47.0, and 10.6 mg oxalate/g creatinine in subjects with PH1, PH2, and PH3 and controls, respectively. Hyp metabolism accounted for 12.8, 32.9, and 14.8 mg oxalate/g creatinine in subjects with PH1, PH2, and PH3, respectively, compared with 1.6 mg oxalate/g creatinine in controls. The contribution of Hyp to urinary oxalate was 15% in controls and 18%, 47%, and 33% in subjects with PH1, PH2, and PH3, respectively. The contribution of Hyp to urinary glycolate was 57% in controls, 30% in subjects with PH1, and <13% in subjects with PH2 or PH3. Conclusions Hyp metabolism differs among PH types and is a major source of oxalate synthesis in individuals with PH2 and PH3. In patients with PH1, who have the highest urinary excretion of oxalate, the major sources of oxalate remain to be identified. Copyright © 2018 by the American Society of Nephrology.

An oxalyl-CoA dependent pathway of oxalate catabolism plays a role in regulating calcium oxalate crystal accumulation and defending against oxalate-secreting phytopathogens in Medicago truncatula

USDA-ARS?s Scientific Manuscript database

Considering the widespread occurrence of oxalate in nature and its broad impact on a host of organisms, it is surprising that so little is known about the turnover of this important acid. In plants, oxalate oxidase is the most well studied enzyme capable of degrading oxalate, but not all plants pos...

Oxalate and phytate of soy foods.

PubMed

Al-Wahsh, Ismail A; Horner, Harry T; Palmer, Reid G; Reddy, Manju B; Massey, Linda K

2005-07-13

The consumption of foods made from soybeans is increasing because of their desirable nutritional value. However, some soy foods contain high concentrations of oxalate and/or phytate. Oxalate is a component of calcium oxalate kidney stones, whereas phytate is an inhibitor of calcium kidney stone formation. Thirty tested commercial soy foods exhibited ranges of 0.02-2.06 mg oxalate/g and 0.80-18.79 mg phytate/g. Commercial soy foods contained 2-58 mg of total oxalate per serving and 76-528 mg phytate per serving. Eighteen of 19 tofu brands and two soymilk brands contained less than 10 mg oxalate per serving, defined as a low oxalate food. Soy flour, textured vegetable soy protein, vegetable soybeans, soy nuts, tempeh, and soynut butter exhibited greater than 10 mg per serving. The correlation between oxalate and phytate in the soy foods was significant (r = 0.71, P < 0.001) indicating that oxalate-rich soy foods also contain higher concentrations of phytate. There also was a significant correlation, based on molar basis, between the divalent ion binding potential of oxalate plus phytate and calcium plus magnesium (r = 0.90, P < 0.001) in soy foods. Soy foods containing small concentrations of oxalate and moderate concentrations of phytate may be advantageous for kidney stone patients or persons with a high risk of kidney stones.

Two New Families of Lanthanide Mixed-Ligand Complexes, Oxalate-Carbonate and Oxalate-Formate: Synthesis and Structure of [Ce(H 2O)] 2(C 2O 4) 2(CO 3)·2.5 H 2O and Ce(C 2O 4)(HCO 2)

NASA Astrophysics Data System (ADS)

Romero, S.; Mosset, A.; Trombe, J. C.

1996-12-01

Two new families of lanthanide complexes associating the ligands oxalate and carbonate or oxalate and formate have been prepared under autogenous pressure at 200°C using a pseudo-hydrothermal method. The two families have been extended to some lanthanides ( Ln): oxalate-carbonate Ln= Ce, Pr, Nd, and Eu; oxalate-formate Ln= La, Ce, and Sm. The starting suspension contains either oxalate or a mixture of oxalate and oxalic acid. The structures have been solved for the element cerium. In both cases, the structure is built up from cerium atoms sharing all their oxygen atoms with oxalate and carbonate or oxalate and formate ligands, thus forming a three-dimensional network. The cerium polyhedra share either faces or edges or corners. The coordination scheme of the oxalate ligands is variable: bischelating, bischelating and monodentate, or bischelating and bismonodentate. The carbonate group acts as a bischelating and bismonodentate ligand while the formate group is chelating and monodentate. The characterization of these two original families by infrared spectra and thermal behavior is presented for some pure phases. A tentative explanation of the synthesis of these two phases will be emphasized.

Loss of Cystic Fibrosis Transmembrane Regulator Impairs Intestinal Oxalate Secretion.

PubMed

Knauf, Felix; Thomson, Robert B; Heneghan, John F; Jiang, Zhirong; Adebamiro, Adedotun; Thomson, Claire L; Barone, Christina; Asplin, John R; Egan, Marie E; Alper, Seth L; Aronson, Peter S

2017-01-01

Patients with cystic fibrosis have an increased incidence of hyperoxaluria and calcium oxalate nephrolithiasis. Net intestinal absorption of dietary oxalate results from passive paracellular oxalate absorption as modified by oxalate back secretion mediated by the SLC26A6 oxalate transporter. We used mice deficient in the cystic fibrosis transmembrane conductance regulator gene (Cftr) to test the hypothesis that SLC26A6-mediated oxalate secretion is defective in cystic fibrosis. We mounted isolated intestinal tissue from C57BL/6 (wild-type) and Cftr -/- mice in Ussing chambers and measured transcellular secretion of [ 14 C]oxalate. Intestinal tissue isolated from Cftr -/- mice exhibited significantly less transcellular oxalate secretion than intestinal tissue of wild-type mice. However, glucose absorption, another representative intestinal transport process, did not differ in Cftr -/- tissue. Compared with wild-type mice, Cftr -/- mice showed reduced expression of SLC26A6 in duodenum by immunofluorescence and Western blot analysis. Furthermore, coexpression of CFTR stimulated SLC26A6-mediated Cl - -oxalate exchange in Xenopus oocytes. In association with the profound defect in intestinal oxalate secretion, Cftr -/- mice had serum and urine oxalate levels 2.5-fold greater than those of wild-type mice. We conclude that defective intestinal oxalate secretion mediated by SLC26A6 may contribute to the hyperoxaluria observed in this mouse model of cystic fibrosis. Future studies are needed to address whether similar mechanisms contribute to the increased risk for calcium oxalate stone formation observed in patients with cystic fibrosis. Copyright © 2016 by the American Society of Nephrology.

Assessment of in vitro oxalate degradation by Lactobacillus species cultured from veterinary probiotics.

PubMed

Cho, Jenny G; Gebhart, Connie J; Furrow, Eva; Lulich, Jody P

2015-09-01

To culture Lactobacillus spp from veterinary probiotics and measure their in vitro oxalate-degrading capacity. 2 commercial veterinary probiotics containing Lactobacillus spp. Lactobacillus spp were cultured anaerobically on selective deMan, Rogosa, Sharpe agar medium and subcultured for speciation by 16S rDNA gene sequencing. Isolates were inoculated into broth containing sodium oxalate (5 mg/L) and incubated anaerobically for 72 hours. An oxalate-degrading isolate of Lactobacillus acidophilus (American Type Culture Collection [ATCC] 53544) was the positive control sample; sterile broth containing a known quantity of sodium oxalate was the negative control sample. Oxalate concentrations were detected with ion chromatography. Oxalate degradation was assessed with Dunnett tests to detect differences in mean oxalate concentration for each isolate, compared with results for the negative control. Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus casei or Lactobacillus zeae (too closely related to differentiate) were isolated from probiotic 1, and L plantarum was isolated from probiotic 2. Sequencing of the 16S rDNA gene confirmed 100% homology to type species. Lactobacillus acidophilus (ATCC 53544) and L acidophilus from probiotic 1 significantly decreased oxalate concentrations by 85.3 and 161.9 mg/L, respectively. Lactobacillus plantarum from probiotics 1 and 2 significantly increased oxalate concentrations by 56.1 and 36.1 mg/L, respectively. Lactobacillus casei did not alter oxalate concentrations. Lactobacillus acidophilus isolates significantly reduced oxalate concentrations. In vivo studies are needed to determine whether probiotics containing L acidophilus decrease urine oxalate concentrations and reduce risk of urolith recurrence in dogs with a history of calcium oxalate urolithiasis.

Vibrational studies in aqueous solutions. Part II. The acid oxalate ion and oxalic acid

NASA Astrophysics Data System (ADS)

Shippey, T. A.

1980-08-01

Assignments for oxalic acid in solution are re-examined. A detailed assignment of the IR and Raman spectra of the acid oxalate ion is presented for the first time. Raman spectroscopy is used to study the first ionization of oxalic acid.

Gateways to clinical trials.

PubMed

Tomillero, A; Moral, M A

2009-04-01

(+)-Dapoxetine hydrochloride, [(123)I]-BZA, 9-Aminocamptothecin; Abacavir sulfate/lamivudine, Adalimumab, Adefovir dipivoxil, Alemtuzumab, Alvocidib hydrochloride, Ambrisentan, Amsilarotene, Anacetrapib, Anakinra, Apricitabine, Aripiprazole, Arsenic trioxide, Atazanavir sulfate, Atazanavir/ritonavir, Atrasentan, Azacitidine; Banoxantrone, Bazedoxifene acetate, Bevacizumab, Bexarotene, Biphasic insulin aspart, Bortezomib, Bosentan, Bromfenac; Cachectin, Calcipotriol/betamethasone dipropionate, Canakinumab, Carfilzomib, CAT-354, CCX-282, Certolizumab pegol, Cetuximab, Choline fenofibrate, Clevudine, Clofarabine, CNTO-328, Corifollitropin alfa, Crofelemer; Daptomycin, Darbepoetin alfa, Darunavir, Dasatinib, Decitabine, Deferasirox, Denosumab, Duloxetine hydrochloride, Dutasteride; Emtricitabine, Enfuvirtide, Entecavir, Epoetin zeta, Erlotinib hydrochloride, Escitalopram oxalate, Eslicarbazepine acetate, Eszopiclone, Etravirine, Everolimus, Exenatide, Ezetimibe, Ezetimibe/simvastatin; Farglitazar, Febuxostat, Fosamprenavir calcium, FX-06; Gabapentin enacarbil, Gefitinib; HIVIS DNA; Imatinib mesylate, INCB- 18424, Indacaterol, Inotuzumab ozogamicin, Insulin detemir; JNJ-26854165; Lacosamide, Landiolol, Laromustine, Lenalidomide, Liposomal doxorubicin, L-NAME, Lopinavir, Lopinavir/ritonavir, Lumiracoxib; Maraviroc, Mepolizumab, Methoxy polyethylene glycol- epoetin-beta, Miglustat, MK-0493, MVA-CMDR, Mycophenolic acid sodium salt; Natalizumab, Nepafenac, Neratinib, Neridronic acid, Nesiritide, Nilotinib hydrochloride monohydrate; Olmesartan medoxomil, Omacetaxine mepesuccinate, Omalizumab; Paclitaxel poliglumex, Palifermin, Patupilone, Pegfilgrastim, Peginterferon alfa-2a, Peginterferon alfa-2b, Peginterferon alfa-2b/ ribavirin, Pemetrexed disodium, PHA-848125, Pitavastatin calcium, Posaconazole, Povidone-iodine liposome complex, Prasugrel, Pregabalin, Prucalopride; Raltegravir potassium, Retigabine, Revaprazan hydrochloride, rhFSH, Rilpivirine, Rivaroxaban, Romidepsin, Rosuvastatin calcium, RWJ-676070; SAR-109659, Sitagliptin phosphate monohydrate, Sorafenib, Stavudine/Lamivudine/Nevirapine, Sunitinib malate; Tadalafil, Telaprevir, Telbivudine, Tenofovir disoproxil fumarate, Tenofovir disoproxil fumarate/emtricitabine, Tenofovir disoproxil fumarate/emtricitabine/efavirenz, Teriparatide, Tigecycline, Tiotropium bromide, Tipifarnib, Tipranavir, Tocilizumab, Trifluridine/TPI; UP-780; Vandetanib, Vardenafil hydrochloride hydrate, Vatalanib succinate, Vitespen, Vorinostat; Yttrium 90 (90Y) ibritumomab tiuxetan; Zoledronic acid monohydrate. Copyright 2009 Prous Science, S.A.U. or its licensors. All rights reserved.

Oxalate analysis methodology for decayed wood

Treesearch

Carol A. Clausen; William Kenealy; Patricia K. Lebow

2008-01-01

Oxalate from partially decayed southern pine wood was analyzed by HPLC or colorimetric assay. Oxalate extraction efficiency, assessed by comparing analysis of whole wood cubes with ground wood, showed that both wood geometries could be extracted with comparable efficiency. To differentiate soluble oxalate from total oxalate, three extraction methods were assessed,...

Total and soluble oxalate content of some Indian spices.

PubMed

Ghosh Das, Sumana; Savage, G P

2012-06-01

Spices, such as cinnamon, cloves, cardamom, garlic, ginger, cumin, coriander and turmeric are used all over the world as flavouring and colouring ingredients in Indian foods. Previous studies have shown that spices contain variable amounts of total oxalates but there are few reports of soluble oxalate contents. In this study, the total, soluble and insoluble oxalate contents of ten different spices commonly used in Indian cuisine were measured. Total oxalate content ranged from 194 (nutmeg) to 4,014 (green cardamom) mg/100 g DM, while the soluble oxalate contents ranged from 41 (nutmeg) to 3,977 (green cardamom) mg/100 g DM. Overall, the percentage of soluble oxalate content of the spices ranged from 4.7 to 99.1% of the total oxalate content which suggests that some spices present no risk to people liable to kidney stone formation, while other spices can supply significant amounts of soluble oxalates and therefore should be used in moderation.

THORIUM OXALATE-URANYL ACETATE COUPLED PROCEDURE FOR THE SEPARATION OF RADIOACTIVE MATERIALS

DOEpatents

Gofman, J.W.

1959-08-11

The recovery of fission products from neutronirradiated uranium is described. The neutron-irradiated uranium is dissolved in acid and thorium oxalate is precipitated in ihe solution formed, whereby the fission products are carried on the thorium oxalate. The separated thorium oxalate precipitate is then dissolved in an aqueous oxalate solution and the solution formed is acidified, limiting ihe excess acidity to a maximum of 2 N, whereby thorium oxalate precipitates and carries lanthanum-rareearth- and alkaline-earth-metal fission products while the zirconium-fission-product remains in solution. This precipitate, too, is dissolved in an aqaeous oxalate solution at elevated temperature, and lanthanum-rare-earth ions are added to the solution whereby lanthanum-rare-earth oxalate forms and the lanthanum-rare-earth-type and alkalineearth-metal-type fission products are carried on the oxalate. The precipitate is separated from the solution.

Impact of Dietary Calcium and Oxalate, and Oxalobacter Formigenes Colonization on Urinary Oxalate Excretion

PubMed Central

Jiang, Juquan; Knight, John; Easter, Linda H.; Neiberg, Rebecca; Holmes, Ross P.; Assimos, Dean G.

2011-01-01

Purpose Enteric colonization with Oxalobacter formigenes, a bacterium whose main energy source is oxalate, has been demonstrated to decrease the risk of recurrent calcium oxalate kidney stone formation. We assessed the impact of diets controlled in calcium and oxalate contents on urinary and fecal analytes in healthy subjects who were naturally colonized with O. formigenes or not colonized with O. formigenes. Materials and Methods A total of 11 O. formigenes colonized and 11 noncolonized subjects were administered diets controlled in calcium and oxalate contents. We assayed 24-hour urine collections and stool samples obtained on the last 4 days of each 1-week diet for stone risk parameters and O. formigenes levels. Mixed model analysis was used to determine the effects of colonization status on these variables. Results Urinary calcium and oxalate excretion were significantly altered by the dietary changes in O. formigenes colonized and noncolonized individuals. Mixed model analysis showed significant interaction between colonization status and oxalate excretion on a low calcium (400 mg daily)/moderate oxalate (250 mg daily) diet (p = 0.026). Urinary oxalate excretion was 19.5% lower in O. formigenes colonized subjects than in noncolonized subjects on the low calcium/moderate oxalate diet (mean ± SE 34.9 ± 2.6 vs 43.6 ± 2.6 mg, p = 0.031). Conclusions Results suggest that O. formigenes colonization decreases oxalate excretion during periods of low calcium and moderate oxalate intake. PMID:21575973

Oxalate exposure provokes HSP 70 response in LLC-PK1 cells, a line of renal epithelial cells: protective role of HSP 70 against oxalate toxicity.

PubMed

Koul, Sweaty; Huang, Meiyi; Bhat, Sidarth; Maroni, Paul; Meacham, Randall B; Koul, Hari K

2008-02-01

We investigated the effects of oxalate on immediate early genes (IEGs) and stress protein HSP 70, commonly induced genes in response to a variety of stresses. LLC-PK1 cells were exposed to oxalate. Gene transcription and translation were monitored by Northern and Western blot analysis. RNA and DNA synthesis were assessed by [(3)H]-uridine and [(3)H]-thymidine incorporation, respectively. Oxalate exposure selectively increased the levels of mRNA encoding IEGs c-myc and c-jun as well as stress protein HSP 70. While expression of c-myc and c-jun was rapid (within 15 min to 2 h) and transient, HSP 70 expression was delayed (approximately 8 h) and stable. Furthermore, oxalate exposure resulted in delayed induction of generalized transcription by 18 h and reinitiation of the DNA synthesis by 24 h of oxalate exposure. Moreover, we show that prior induction of HSP 70 by mild hypertonic exposure protected the cells from oxalate toxicity. To the best of our knowledge this is the first study to demonstrate rapid IEG response and delayed heat-shock response to oxalate toxicity and protective role of HSP 70 against oxalate toxicity to renal epithelial cells. Oxalate, a metabolic end product, induces IEGs c-myc and c-jun and a delayed HSP 70 expression; While IEG expression may regulate additional genetic responses to oxalate, increased HSP 70 expression would serve an early protective role during oxalate stress.

Effect of cinnamon and turmeric on urinary oxalate excretion, plasma lipids, and plasma glucose in healthy subjects.

PubMed

Tang, Minghua; Larson-Meyer, D Enette; Liebman, Michael

2008-05-01

High oxalate intake resulting from consuming supplemental doses of cinnamon and turmeric may increase risk of hyperoxaluria, a significant risk factor for urolithiasis. This study assessed urinary oxalate excretion from supplemental doses of cinnamon and turmeric as well as changes in fasting plasma glucose, cholesterol, and triacylglycerol concentrations. Eleven healthy subjects, aged 21-38 y, participated in an 8-wk, randomly assigned, crossover study that involved the ingestion of supplemental doses of cinnamon and turmeric for 4-wk periods that provided 55 mg oxalate/d. Oxalate load tests, which entailed the ingestion of a 63-mg dose of oxalate from the test spices, were performed after each 4-wk experimental period and at the study onset with water only (control treatment). Fasting plasma glucose and lipid concentrations were also assessed at these time points. Compared with the cinnamon and control treatments, turmeric ingestion led to a significantly higher urinary oxalate excretion during the oxalate load tests. There were no significant changes in fasting plasma glucose or lipids in conjunction with the 4-wk periods of either cinnamon or turmeric supplementation. The percentage of oxalate that was water soluble differed markedly between cinnamon (6%) and turmeric (91%), which appeared to be the primary cause of the greater urinary oxalate excretion/oxalate absorption from turmeric. The consumption of supplemental doses of turmeric, but not cinnamon, can significantly increase urinary oxalate levels, thereby increasing risk of kidney stone formation in susceptible individuals.

Transcellular oxalate and Cl− absorption in mouse intestine is mediated by the DRA anion exchanger Slc26a3, and DRA deletion decreases urinary oxalate

PubMed Central

Freel, Robert W.; Whittamore, Jonathan M.

2013-01-01

Active transcellular oxalate transport in the mammalian intestine contributes to the homeostasis of this important lithogenic anion. Several members of the Slc26a gene family of anion exchangers have a measurable oxalate affinity and are expressed along the gut, apically and basolaterally. Mouse Slc26a6 (PAT1) targets to the apical membrane of enterocytes in the small intestine, and its deletion results in net oxalate absorption and hyperoxaluria. Apical exchangers of the Slc26a family that mediate oxalate absorption have not been established, yet the Slc26a3 [downregulated in adenoma (DRA)] protein is a candidate mediator of oxalate uptake. We evaluated the role of DRA in intestinal oxalate and Cl− transport by comparing unidirectional and net ion fluxes across short-circuited segments of small (ileum) and large (cecum and distal colon) intestine from wild-type (WT) and DRA knockout (KO) mice. In WT mice, all segments demonstrated net oxalate and Cl− absorption to varying degrees. In KO mice, however, all segments exhibited net anion secretion, which was consistently, and solely, due to a significant reduction in the absorptive unidirectional fluxes. In KO mice, daily urinary oxalate excretion was reduced 66% compared with that in WT mice, while urinary creatinine excretion was unchanged. We conclude that DRA mediates a predominance of the apical uptake of oxalate and Cl− absorbed in the small and large intestine of mice under short-circuit conditions. The large reductions in urinary oxalate excretion underscore the importance of transcellular intestinal oxalate absorption, in general, and, more specifically, the importance of the DRA exchanger in oxalate homeostasis. PMID:23886857

YfdW and YfdU Are Required for Oxalate-Induced Acid Tolerance in Escherichia coli K-12

PubMed Central

Fontenot, Elise M.; Ezelle, Karen E.; Gabreski, Lauren N.; Giglio, Eleanor R.; McAfee, John M.; Mills, Alexandria C.; Qureshi, Maryam N.; Salmon, Kristin M.

2013-01-01

Escherichia coli has several mechanisms for surviving low-pH stress. We report that oxalic acid, a small-chain organic acid (SCOA), induces a moderate acid tolerance response (ATR) in two ways. Adaptation of E. coli K-12 at pH 5.5 with 50 mM oxalate and inclusion of 25 mM oxalate in pH 3.0 minimal challenge medium separately conferred protection, with 67% ± 7% and 87% ± 17% survival after 2 h, respectively. The combination of oxalate adaptation and oxalate supplementation in the challenge medium resulted in increased survival over adaptation or oxalate in the challenge medium alone. The enzymes YfdW, a formyl coenzyme A (CoA) transferase, and YfdU, an oxalyl-CoA decarboxylase, are required for the adaptation effect but not during challenge. Unlike other SCOAs, this oxalate ATR is not a part of the RpoS regulon but appears to be linked to the signal protein GadE. We theorize that this oxalate ATR could enhance the pathogenesis of virulent E. coli consumed with oxalate-containing foods like spinach. PMID:23335415

Effects of Juice Processing on Oxalate Contents in Carambola Juice Products.

PubMed

Huynh, Nha K; Nguyen, Ha V H

2017-09-01

Effects of processing methods including pressing, enzyme-assisted extraction, lactic acid fermentation by Lactobacillus acidophilus, and alcohol fermentation by Saccharomyces cerevisiae on total and soluble oxalate contents of carambola juices were studied. In comparison with pressing, the use of enzyme increased juice yields (15.89-17.29%), but resulted in higher total oxalate (1.60-1.73 times) and soluble oxalate contents (1.16-1.49 times). In addition, extension of enzyme incubation periods led to an increase in soluble oxalate contents in the products (p < 0.05). On the other hand, alcohol fermentation with Saccharomyces cerevisiae from 1 to 5 weeks reduced 37-58% of total oxalate and 39-59% of soluble oxalate contents. Prolonged fermentation also demonstrated better reduction of oxalate contents. Meanwhile, lactic acid fermentation using Lactobacillus acidophilus had no effects on total and soluble oxalate contents in carambola juices. These results suggested that carambola juice products should only be consumed moderately, and that alcohol fermentation could be a potential method to reduce oxalate contents in foods in order to prevent the risks of forming kidney stones.

Lowering urinary oxalate excretion to decrease calcium oxalate stone disease

PubMed Central

Knight, John; Assimos, Dean G.

2016-01-01

Dietary modifications should be considered as a first line approach in the treatment of idiopathic calcium oxalate nephrolithiasis. The amounts of oxalate and calcium consumed in the diet are significant factors in the development of the disease due to their impact on urinary oxalate excretion. There are a number of strategies that can be employed to reduce oxalate excretion. The consumption of oxalate-rich foods should be avoided and calcium intake adjusted to 1000–1200 mg/day. To encourage compliance it should be emphasized to patients that they be vigilant with this diet as a deviation in any meal or snack could potentially result in significant stone growth. The evidence underlying these two modifications is outlined and other strategies to reduce urinary oxalate excretion are reviewed. PMID:26614109

DETERMINATION OF OXALATE ION DOPANT LEVEL IN POLYPYRROLE USING FT-IR

PubMed Central

Benally, Kristal J.; GreyEyes, Shawn D.; McKenzie, Jason T.

2014-01-01

A pellet method using standard addition and FT-IR was used to estimate oxalate ion doping levels in electrosynthesized polypyrrole. The method is useful for materials where removal of analyte from an insoluble material is problematic. Here, electrosynthesized oxalate doped polypyrrole is dispersed in potassium bromide. Spikes of sodium oxalate are added and the mixtures pressed into pellets. The oxalate carbonyl absorption peak is then used to quantify the amount of oxalate present in the polypyrrole. The mass fraction of oxalate dopant in polypyrrole was determined to be 0.4 ± 0.1 % and coincides with the original synthesis solution composition. PMID:25598749

Selective Rac1 inhibition protects renal tubular epithelial cells from oxalate-induced NADPH oxidase-mediated oxidative cell injury

PubMed Central

Thamilselvan, Vijayalakshmi; Menon, Mani

2013-01-01

Oxalate-induced oxidative cell injury is one of the major mechanisms implicated in calcium oxalate nucleation, aggregation and growth of kidney stones. We previously demonstrated that oxalate-induced NADPH oxidase-derived free radicals play a significant role in renal injury. Since NADPH oxidase activation requires several regulatory proteins, the primary goal of this study was to characterize the role of Rac GTPase in oxalate-induced NADPH oxidase-mediated oxidative injury in renal epithelial cells. Our results show that oxalate significantly increased membrane translocation of Rac1 and NADPH oxidase activity of renal epithelial cells in a time-dependent manner. We found that NSC23766, a selective inhibitor of Rac1, blocked oxalate-induced membrane translocation of Rac1 and NADPH oxidase activity. In the absence of Rac1 inhibitor, oxalate exposure significantly increased hydrogen peroxide formation and LDH release in renal epithelial cells. In contrast, Rac1 inhibitor pretreatment, significantly decreased oxalate-induced hydrogen peroxide production and LDH release. Furthermore, PKC α and δ inhibitor, oxalate exposure did not increase Rac1 protein translocation, suggesting that PKC resides upstream from Rac1 in the pathway that regulates NADPH oxidase. In conclusion, our data demonstrate for the first time that Rac1-dependent activation of NADPH oxidase might be a crucial mechanism responsible for oxalate-induced oxidative renal cell injury. These findings suggest that Rac1 signaling plays a key role in oxalate-induced renal injury, and may serve as a potential therapeutic target to prevent calcium oxalate crystal deposition in stone formers and reduce recurrence. PMID:21814770

LITERATURE REVIEW FOR OXALATE OXIDATION PROCESSES AND PLUTONIUM OXALATE SOLUBILITY

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

Nash, C.

2012-02-03

A literature review of oxalate oxidation processes finds that manganese(II)-catalyzed nitric acid oxidation of oxalate in precipitate filtrate is a viable and well-documented process. The process has been operated on the large scale at Savannah River in the past, including oxidation of 20 tons of oxalic acid in F-Canyon. Research data under a variety of conditions show the process to be robust. This process is recommended for oxalate destruction in H-Canyon in the upcoming program to produce feed for the MOX facility. Prevention of plutonium oxalate precipitation in filtrate can be achieved by concentrated nitric acid/ferric nitrate sequestration of oxalate.more » Organic complexants do not appear practical to sequester plutonium. Testing is proposed to confirm the literature and calculation findings of this review at projected operating conditions for the upcoming campaign. H Canyon plans to commence conversion of plutonium metal to low-fired plutonium oxide in 2012 for eventual use in the Mixed Oxide Fuel (MOX) Facility. The flowsheet includes sequential operations of metal dissolution, ion exchange, elution, oxalate precipitation, filtration, and calcination. All processes beyond dissolution will occur in HB-Line. The filtration step produces an aqueous filtrate that may have as much as 4 M nitric acid and 0.15 M oxalate. The oxalate needs to be removed from the stream to prevent possible downstream precipitation of residual plutonium when the solution is processed in H Canyon. In addition, sending the oxalate to the waste tank farm is undesirable. This report addresses the processing options for destroying the oxalate in existing H Canyon equipment.« less

Changes in dream experience in relation with antidepressant escitalopram treatment in depressed female patients: a preliminary study.

PubMed

Quartini, Adele; Anastasia, Annalisa; Bersani, Francesco Saverio; Melcore, Claudia; Albano, Gabriella; Colletti, Chiara; Valeriani, Giuseppe; Bersani, Giuseppe

2014-01-01

Sleep disturbances have long been considered as a cardinal symptom of endogenous depression and dreams in depressed patients usually differ from those of healthy people. The aim of the present study was to investigate dream subjective experiences and their modifications in relation to clinical response in a group of escitalopram-treated depressed patients. Twenty-seven female patients meeting DSM-IV-TR criteria for Major Depressive Disorder (MDD) and starting SSRI therapy were included in the study. Data about psychopathological status and dreaming subjective experiences were collected at baseline (T0), 4 weeks after the beginning of the treatment (T1) and after further 4 weeks of therapy (T2). At T0 dream experience was impaired and negatively toned. Concomitantly with the decrease of symptoms severity, the 8-week escitalopram treatment yielded to significant improvements in the recall of both quantity and quality of dreams; those patients whit lower clinical benefits kept on reporting impaired dream experiences. The results of the present study evidence how the changes in some specific dreaming characteristics, such as the subjective recall of dream activity, the dream recall quality, the dream emotional content and the dream complexity represent reliable markers of the effectiveness of antidepressant therapy.

Interaction of different antidepressants with acute and chronic methadone in mice, and possible clinical implications.

PubMed

Schreiber, Shaul; Barak, Yonatan; Hostovsky, Avner; Baratz-Goldstein, Renana; Volis, Ina; Rubovitch, Vardit; Pick, Chaim G

2014-04-01

We studied the interaction of a single dose of different antidepressant medications with a single (acute) dose or implanted mini-pump (chronic) methadone administration in mice, using the hotplate assay. For the acute experiment, subthreshold doses of six antidepressant drugs were administered separately with a single dose of methadone. The addition of a subthreshold dose of desipramine or clomipramine to methadone produced significant augmentation of the methadone effect with each drug (p < 0.05). Fluvoxamine given at a fixed subthreshold dose induced a synergistic effect only with a low methadone dose. Escitalopram, reboxetine and venlafaxine given separately, each at a fixed subthreshold dose, induced no interaction. Possible clinical implications of these findings are that while escitalopram, reboxetine and venlafaxine do not affect methadone's antinociception in mice and are safe to be given together with methadone when indicated, fluvoxamine, clomipramine and desipramine considerably augment methadone-induced effects and should be avoided in this population due to the risk of inducing opiate overdose. For the chromic experiment, when a subthreshold dose of either escitalopram, desipramine or clomipramine was injected to mice following 2 weeks of methadone administration with the mini-pump, none of the antidepressant drugs strengthened methadone's analgesic effect. Further studies are needed before possible clinical implications can be drawn.

In vivo oxalate degradation by liposome encapsulated oxalate oxidase in rat model of hyperoxaluria

PubMed Central

Dahiya, Tulika; Pundir, C.S.

2013-01-01

Background & objectives: High level of urinary oxalate substantially increases the risk of hyperoxaluria, a significant risk factor for urolithiasis. The primary goal of this study was to reduce urinary oxalate excretion employing liposome encapsulated oxalate oxidase in animal model. Methods: A membrane bound oxalate oxidase was purified from Bougainvillea leaves. The enzyme in its native form was less effective at the physiological pH of the recipient animal. To increase its functional viability, the enzyme was immobilized on to ethylene maleic anhydride (EMA). Rats were injected with liposome encapsulated EMA- oxalate oxidase and the effect was observed on degradation of oxalic acid. Results: The enzyme was purified to apparent homogeneity with 60-fold purification and 31 per cent yield. The optimum pH of EMA-derivative enzyme was 6.0 and it showed 70 per cent of its optimal activity at pH 7.0. The EMA-bound enzyme encapsulated into liposome showed greater oxalate degradation in 15 per cent casein vitamin B6 deficient fed rats as compared with 30 per cent casein vitamin B6 deficient fed rats and control rats. Interpretation & conclusions: EMA-oxalate oxidase encapsulated liposome caused oxalate degradation in experimental hyperoxaluria indicating that the enzyme could be used as a therapeutic agent in hyperoxaluria leading to urinary stones. PMID:23481063

Effect of Dietary Oxalate on the Gut Microbiota of the Mammalian Herbivore Neotoma albigula

PubMed Central

Oakeson, Kelly F.; Dale, Colin; Dearing, M. Denise

2016-01-01

Diet is one of the primary drivers that sculpts the form and function of the mammalian gut microbiota. However, the enormous taxonomic and metabolic diversity held within the gut microbiota makes it difficult to isolate specific diet-microbe interactions. The objective of the current study was to elucidate interactions between the gut microbiota of the mammalian herbivore Neotoma albigula and dietary oxalate, a plant secondary compound (PSC) degraded exclusively by the gut microbiota. We quantified oxalate degradation in N. albigula fed increasing amounts of oxalate over time and tracked the response of the fecal microbiota using high-throughput sequencing. The amount of oxalate degraded in vivo was linearly correlated with the amount of oxalate consumed. The addition of dietary oxalate was found to impact microbial species diversity by increasing the representation of certain taxa, some of which are known to be capable of degrading oxalate (e.g., Oxalobacter spp.). Furthermore, the relative abundances of 117 operational taxonomic units (OTU) exhibited a significant correlation with oxalate consumption. The results of this study indicate that dietary oxalate induces complex interactions within the gut microbiota that include an increase in the relative abundance of a community of bacteria that may contribute either directly or indirectly to oxalate degradation in mammalian herbivores. PMID:26896138

Intestinal Adaptations in Chronic Kidney Disease and the Influence of Gastric Bypass Surgery

PubMed Central

Hatch, Marguerite

2015-01-01

Studies have shown that compensatory adaptations in gastrointestinal oxalate transport can impact the amount of oxalate excreted by the kidney. Hyperoxaluria is a major risk factor in the formation of kidney stones and oxalate is derived from both the diet as well as from liver metabolism of glyoxylate. Although the intestine generally absorbs oxalate from dietary sources, and can contribute as much as 50% of urinary oxalate, enteric oxalate elimination plays a significant role when renal function is compromised. While the mechanistic basis for these changes in the direction of intestinal oxalate movements in chronic renal failure involves an up-regulation of angiotensin II (ANG) receptors in the large intestine, enteric secretion/excretion of oxalate can also occur by mechanisms that are independent of ANG II. Most notably, the commensal bacterium Oxalobacter sp. interacts with the host enterocyte and promotes the movement of oxalate from blood into the lumen resulting in the beneficial effect of significantly lowering urinary oxalate excretion. Changes in the passive permeability of the intestine such as in steatorrhea and following gastric bypass also promote oxalate absorption and hyperoxaluria. In summary, this report highlights the two-way physiological signaling between the gut and the kidney which may help to alleviate the consequences of certain kidney diseases. PMID:24951497

What is the threshold for symptomatic response and remission for major depressive disorder, panic disorder, social anxiety disorder, and generalized anxiety disorder?

PubMed

Bandelow, Borwin; Baldwin, David S; Dolberg, Ornah T; Andersen, Henning Friis; Stein, Dan J

2006-09-01

Symptom-free remission is a goal for treatment in depression and anxiety disorders, but there is no consensus regarding the threshold for determining remission in individual disorders. We sought to determine these thresholds by comparing, in a post hoc analysis, scores on the Clinical Global Impressions scale (CGI) and disorder-specific symptom severity rating scales from all available studies of the treatment of major depressive disorder, panic disorder, generalized anxiety disorder, and social anxiety disorder with the same medication (escitalopram). We also sought to compare the standardized effect sizes of escitalopram for these 4 psychiatric disorders. Raw data from all randomized, double-blind, placebo-controlled, acute treatment studies sponsored by H. Lundbeck A/S (Copenhagen, Denmark) or Forest Laboratories, Inc. (New York, N.Y.), published through March 1, 2004, with patients treated with escitalopram for DSM-IV major depressive disorder (5 studies), panic disorder (1 study), generalized anxiety disorder (4 studies), or social anxiety disorder (2 studies) were compared with regard to the standardized effect sizes of change in CGI score and scores on rating scales that represent the "gold standard" for assessment of these disorders (the Montgomery-Asberg Depression Rating Scale, the Panic and Agoraphobia Scale, the Hamilton Rating Scale for Anxiety, and the Liebowitz Social Anxiety Scale, respectively). In all indications, treatment with escitalopram showed differences from placebo in treatment effect from 0.32 to 0.59 on the CGI-S and CGI-I and standardized effect sizes from 0.32 to 0.50 on the standard rating scales. There were no significant differences among the different disorders. Moderate to high correlations were found between scores on the CGI and the standard scales. The corresponding standard scale scores for CGI-defined "response" and "remission" were determined. Comparison of scores on the standard scales and scores on the CGI suggest that the traditional definition of response (i.e., a 50% reduction in a standard scale) may be too conservative.

Healthcare utilization and costs incurred by patients with major depression after being switched from escitalopram to another SSRI for non-medical reasons.

PubMed

Wu, Eric Q; Ben-Hamadi, Rym; Yu, Andrew P; Tang, Jackson; Haim Erder, M; Bose, Anjana

2010-01-01

To compare healthcare utilization and costs for major depressive disorder (MDD) patients treated with escitalopram and who were switched to another SSRI for non-medical reasons versus those who did not switch. Patients were identified in the Ingenix Impact Database (2003-2006). The analysis group included patients who remained on escitalopram for ≥ 90 days and switched to another SSRI within 45 days of end of supply days for non-medical reasons; the control group included matched individuals who did not switch within 45 days. Switching for medical reasons was defined as switching within 7 days after having a hospitalization, an emergency room (ER) visit, or a psychotherapy visit. Outcomes (all-cause and MDD-related) were analyzed over 3 months and included use of hospital, ER, outpatient visits and professional services, and healthcare costs. Outcomes were compared between the two groups using descriptive statistics and regression analyses controlling for differences in baseline characteristics. Costs were inflation adjusted to 2006 US dollars. The study included 2,805 matched pairs. Compared to controls, switchers had higher rates of all-cause and MDD-related hospitalizations (relative risk [RR] = 1.4 and 2.0, respectively) and all-cause and MDD-related ER visits (RR = 1.2 and 1.6, respectively, all p ≤ 0.05). Results from multivariate analyses show that switchers had higher medical costs (+$138), drug costs (+$149) and total healthcare costs (+$322) compared to patients in the control group (all p < 0.0001). This study's limitations include its short observational period and definition of switching for non-medical reasons. Patients who were switched to another SSRI for non-medical reasons after being stabilized on escitalopram used more resources and had higher healthcare costs within 3 months of switching than patients who did not switch.

Microbiota Diversification and Crash Induced by Dietary Oxalate in the Mammalian Herbivore Neotoma albigula

PubMed Central

Dale, Colin; Dearing, M. Denise

2017-01-01

ABSTRACT Oxalate, broadly found in both dietary and endogenous sources, is a primary constituent in 80% of kidney stones, an affliction that has tripled in prevalence over the last 40 years. Oxalate-degrading bacteria within the gut microbiota can mitigate the effects of oxalate and are negatively correlated with kidney stone formation, but bacteriotherapies involving oxalate-degrading bacteria have met with mixed results. To inform the development of more effective and consistent bacteriotherapies, we sought to quantify the interactions and limits between oxalate and an oxalate-adapted microbiota from the wild mammalian herbivore Neotoma albigula (woodrat), which consumes a high-oxalate diet in the wild. We tracked the microbiota over a variable-oxalate diet ranging from 0.2% to 12%, with the upper limit approximating 10× the level of human consumption. The N. albigula microbiota was capable of degrading ~100% of dietary oxalate regardless of the amount consumed. However, the microbiota exhibited significant changes in diversity dynamically at the operational taxonomic unit (OTU), family, and community levels in accordance with oxalate input. Furthermore, a cohesive microbial network was stimulated by the consumption of oxalate and exhibited some resistance to the effects of prolonged exposure. This study demonstrates that the oxalate-adapted microbiota of N. albigula exhibits a very high level of degradation and tolerance for oxalate. IMPORTANCE The bacteria associated with mammalian hosts exhibit extensive interactions with overall host physiology and contribute significantly to the health of the host. Bacteria are vital to the mitigation of the toxic effects of oxalate specifically as mammals do not possess the enzymes to degrade this compound, which is present in the majority of kidney stones. Contrary to the body of literature on a few oxalate-degrading specialists, our work illustrates that oxalate stimulates a broad but cohesive microbial network in a dose-dependent manner. The unique characteristics of the N. albigula microbiota make it an excellent source for the development of bacteriotherapies to inhibit kidney stone formation. Furthermore, this work successfully demonstrates methods to identify microbial networks responsive to specific toxins, their limits, and important elements such as microbial network cohesivity and architecture. These are necessary steps in the development of targeted bacteriotherapies. PMID:29062900

Isolation of oxalic acid tolerating fungi and decipherization of its potential to control Sclerotinia sclerotiorum through oxalate oxidase like protein.

PubMed

Yadav, Shivani; Srivastava, Alok K; Singh, Dhanajay P; Arora, Dilip K

2012-11-01

Oxalic acid plays major role in the pathogenesis by Sclerotinia sclerotiorum; it lowers the pH of nearby environment and creates the favorable condition for the infection. In this study we examined the degradation of oxalic acid through oxalate oxidase and biocontrol of Sclerotinia sclerotiorum. A survey was conducted to collect the rhizospheric soil samples from Indo-Gangetic Plains of India to isolate the efficient fungal strains able to tolerate oxalic acid. A total of 120 fungal strains were isolated from root adhering soils of different vegetable crops. Out of 120 strains a total of 80 isolates were able to grow at 10 mM of oxalic acid whereas only 15 isolates were grow at 50 mM of oxalic acid concentration. Then we examined the antagonistic activity of the 15 isolates against Sclerotinia sclerotiorum. These strains potentially inhibit the growth of the test pathogen. A total of three potential strains and two standard cultures of fungi were tested for the oxalate oxidase activity. Strains S7 showed the maximum degradation of oxalic acid (23 %) after 60 min of incubation with fungal extract having oxalate oxidase activity. Microscopic observation and ITS (internally transcribed spacers) sequencing categorized the potential fungal strains into the Aspergillus, Fusarium and Trichoderma. Trichoderma sp. are well studied biocontrol agent and interestingly we also found the oxalate oxidase type activity in these strains which further strengthens the potentiality of these biocontrol agents.

Pseudomonas fluorescens ATCC 13525 Containing an Artificial Oxalate Operon and Vitreoscilla Hemoglobin Secretes Oxalic Acid and Solubilizes Rock Phosphate in Acidic Alfisols

PubMed Central

Archana, G.; Naresh Kumar, G.

2014-01-01

Oxalate secretion was achieved in Pseudomonas fluorescens ATCC 13525 by incorporation of genes encoding Aspergillus niger oxaloacetate acetyl hydrolase (oah), Fomitopsis plaustris oxalate transporter (FpOAR) and Vitreoscilla hemoglobin (vgb) in various combinations. Pf (pKCN2) transformant containing oah alone accumulated 19 mM oxalic acid intracellularly but secreted 1.2 mM. However, in the presence of an artificial oxalate operon containing oah and FpOAR genes in plasmid pKCN4, Pf (pKCN4) secreted 13.6 mM oxalate in the medium while 3.6 mM remained inside. This transformant solubilized 509 μM of phosphorus from rock phosphate in alfisol which is 4.5 fold higher than the Pf (pKCN2) transformant. Genomic integrants of P. fluorescens (Pf int1 and Pf int2) containing artificial oxalate operon (plac-FpOAR-oah) and artificial oxalate gene cluster (plac-FpOAR-oah, vgb, egfp) secreted 4.8 mM and 5.4 mM oxalic acid, released 329 μM and 351 μM P, respectively, in alfisol. The integrants showed enhanced root colonization, improved growth and increased P content of Vigna radiata plants. This study demonstrates oxalic acid secretion in P. fluorescens by incorporation of an artificial operon constituted of genes for oxalate synthesis and transport, which imparts mineral phosphate solubilizing ability to the organism leading to enhanced growth and P content of V. radiata in alfisol soil. PMID:24705024

SEPARATION OF TRANSURANIC ELEMENTS FROM RARE EARTH COMPOUNDS

DOEpatents

Kohman, T.P.

1961-11-21

A process of separating neptunium and plutonium values from rare earths and alkaline earth fission products present on a solid mixed actinide carrier (Th or U(IV) oxalate or fluoride) --fission product carrier (LaF/sub 3/, CeF/sub 3/, SrF/sub 2/, CaF/sub 2/, YF/sub 3/, La oxalate, cerous oxalate, Sr oxalate, Ca oxalate or Y oxalate) by extraction of the actinides at elevated temperature with a solution of ammonium fluoride and/or ammonium oxalate is described. Separation of the fission-product-containing carriers from the actinide solution formed and precipitation of the neptunium and plutonium from the solution with mineral acid are also accomplished. (AEC)

Ascorbic Acid Intake and Oxalate Synthesis

PubMed Central

Knight, John; Madduma-Liyanage, Kumudu; Mobley, James A.; Assimos, Dean G.; Holmes, Ross P.

2016-01-01

In humans approximately 60 mg of ascorbic acid (AA) breaks down in the body each day and has to be replaced by a dietary intake of 70 mg in females and 90 mg in males to maintain optimal health and AA homeostasis. The breakdown of AA is non-enzymatic and results in oxalate formation. The exact amount of oxalate formed has been difficult to ascertain primarily due to the limited availability of healthy human tissue for such research and the difficulty in measuring AA and its breakdown products. The breakdown of 60 mg of AA to oxalate could potentially result in the formation of up to 30 mg oxalate per day. This exceeds our estimates of the endogenous production of 10 – 25 mg oxalate per day, indicating that degradative pathways that do not form oxalate exist. In this review we examine what is known about the pathways of AA metabolism and how oxalate forms. We further identify how gaps in our knowledge may be filled to more precisely determine the contribution of AA breakdown to oxalate production in humans. The use of stable isotopes of AA to directly assess the conversion of vitamin to oxalate should help fill this void. PMID:27002809

Downregulation of NF-κB and PCNA in the regulatory pathways of apoptosis by cyclooxygenase-2 inhibitors in experimental lung cancer.

PubMed

Setia, Shruti; Sanyal, Sankar Nath

2012-10-01

Non-steroidal anti-inflammatory drugs (NSAIDs) are emerging as novel chemopreventive agents against a variety of cancers owing to their capability in blocking the tumor development by cellular proliferation, angiogenesis and by promoting apoptosis. The present study further explored the comparative role of a traditional NSAID, indomethacin and a newly developed coxib, etoricoxib against 9,10-dimethylbenz(a)anthracene (DMBA)-induced lung carcinogenesis in rats. Morphological and histological analysis revealed the occurrence of tumors and lesions along with constricted alveolar spaces in the DMBA treated animals which were largely corrected both by indomethacin and etoricoxib. COX-1 was found to be uniformly expressed in all the groups while COX-2 levels were raised prominently in the DMBA treated animals. Proliferation, as studied by PCNA expression was found to be markedly increased in the DMBA group as compared to the others. Increased NF-κB expression in the DMBA group was found to correct with the co-administration of NSAIDs. Also, fluorescent co-staining of the isolated lung cells revealed a significantly decreased apoptosis and altered mitochondrial membrane potential. In conclusion, these parameters indicate to the chemopreventive action of the two NSAIDs studied in lung cancer and as their mechanism of action suggests, can be achievable both by COX-dependent and COX-independent pathways.

Oxalobacter formigenes–Derived Bioactive Factors Stimulate Oxalate Transport by Intestinal Epithelial Cells

PubMed Central

Arvans, Donna; Jung, Yong-Chul; Antonopoulos, Dionysios; Koval, Jason; Granja, Ignacio; Bashir, Mohamed; Karrar, Eltayeb; Roy-Chowdhury, Jayanta; Musch, Mark; Asplin, John; Chang, Eugene

2017-01-01

Hyperoxaluria is a major risk factor for kidney stones and has no specific therapy, although Oxalobacter formigenes colonization is associated with reduced stone risk. O. formigenes interacts with colonic epithelium and induces colonic oxalate secretion, thereby reducing urinary oxalate excretion, via an unknown secretagogue. The difficulties in sustaining O. formigenes colonization underscore the need to identify the derived factors inducing colonic oxalate secretion. We therefore evaluated the effects of O. formigenes culture conditioned medium (CM) on apical 14C-oxalate uptake by human intestinal Caco-2-BBE cells. Compared with control medium, O. formigenes CM significantly stimulated oxalate uptake (>2.4-fold), whereas CM from Lactobacillus acidophilus did not. Treating the O. formigenes CM with heat or pepsin completely abolished this bioactivity, and selective ultrafiltration of the CM revealed that the O. formigenes–derived factors have molecular masses of 10–30 kDa. Treatment with the protein kinase A inhibitor H89 or the anion exchange inhibitor 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid completely blocked the CM-induced oxalate transport. Knockdown of the oxalate transporter SLC26A6 also significantly restricted the induction of oxalate transport by CM. In a mouse model of primary hyperoxaluria type 1, rectal administration of O. formigenes CM significantly reduced (>32.5%) urinary oxalate excretion and stimulated (>42%) distal colonic oxalate secretion. We conclude that O. formigenes–derived bioactive factors stimulate oxalate transport in intestinal cells through mechanisms including PKA activation. The reduction in urinary oxalate excretion in hyperoxaluric mice treated with O. formigenes CM reflects the in vivo retention of biologic activity and the therapeutic potential of these factors. PMID:27738124

Extracellular nucleotides inhibit oxalate transport by human intestinal Caco-2-BBe cells through PKC-δ activation

PubMed Central

Amin, Ruhul; Sharma, Sapna; Ratakonda, Sireesha

2013-01-01

Nephrolithiasis remains a major health problem in Western countries. Seventy to 80% of kidney stones are composed of calcium oxalate, and small changes in urinary oxalate affect risk of kidney stone formation. Intestinal oxalate secretion mediated by the anion exchanger SLC26A6 plays an essential role in preventing hyperoxaluria and calcium oxalate nephrolithiasis, indicating that understanding the mechanisms regulating intestinal oxalate transport is critical for management of hyperoxaluria. Purinergic signaling modulates several intestinal processes through pathways including PKC activation, which we previously found to inhibit Slc26a6 activity in mouse duodenal tissue. We therefore examined whether purinergic stimulation with ATP and UTP affects oxalate transport by human intestinal Caco-2-BBe (C2) cells. We measured [14C]oxalate uptake in the presence of an outward Cl− gradient as an assay of Cl−/oxalate exchange activity, ≥50% of which is mediated by SLC26A6. We found that ATP and UTP significantly inhibited oxalate transport by C2 cells, an effect blocked by the PKC inhibitor Gö-6983. Utilizing pharmacological agonists and antagonists, as well as PKC-δ knockdown studies, we observed that ATP inhibits oxalate transport through the P2Y2 receptor, PLC, and PKC-δ. Biotinylation studies showed that ATP inhibits oxalate transport by lowering SLC26A6 surface expression. These findings are of potential relevance to pathophysiology of inflammatory bowel disease-associated hyperoxaluria, where supraphysiological levels of ATP/UTP are expected and overexpression of the P2Y2 receptor has been reported. We conclude that ATP and UTP inhibit oxalate transport by lowering SLC26A6 surface expression in C2 cells through signaling pathways including the P2Y2 purinergic receptor, PLC, and PKC-δ. PMID:23596171

Further Studies on Oxalic Acid Biosynthesis in Oxalate-accumulating Plants 1

PubMed Central

Nuss, Richard F.; Loewus, Frank A.

1978-01-01

l-Ascorbic acid functions as a precursor of oxalic acid in several oxalate-accumulating plants. The present study extends this observation to include Rumex crispus L. (curly dock), Amaranthus retroflexus L. (red root pigweed), Chenopodium album L. (lamb's-quarters), Beta vulgaris L. (sugar beet), Halogeton glomeratus M. Bieb. (halogeton), and Rheum rhabarbarum L. (rhubarb). Several species with low oxalate content are also examined. When l-[1-14C]ascorbic acid is supplied to young seedlings of R. crispus or H. glomeratus, a major portion of the 14C is released over a 24-hour period as 14CO2 and only a small portion is recovered as [14C]oxalate, unlike cuttings from 2- or 4-month-old plants which retain a large part of the 14C as [14C]oxalic acid and release very little 14CO2. Support for an intermediate role of oxalate in the release of 14CO2 from l-[1-14C]ascorbic acid is seen in the rapid release of 14CO2 by R. crispus and H. glomeratus seedlings labeled with [14C]oxalic acid. The common origin of oxalic acid carbon in the C1 and C2 fragment from l-ascorbic acid is demonstrated by comparison of 14C content of oxalic acid in several oxalate-accumulators after cuttings or seedlings are supplied equal amounts of l-[1-14C]- or l-[UL-14C]ascorbic acid. Theoretically, l-[1-14C]ascorbic acid will produce labeled oxalic acid containing three times as much 14C as l-[UL-14C]ascorbic acid when equal amounts of label are provided. Experimentally, a ratio of 2.7 ± 0.5 is obtained in duplicate experiments with six different species. PMID:16660342

Metabolic Conversion of l-Ascorbic Acid to Oxalic Acid in Oxalate-accumulating Plants 1

PubMed Central

Yang, Joan C.; Loewus, Frank A.

1975-01-01

l-Ascorbic acid-1-14C and its oxidation product, dehydro-l-ascorbic acid, produced labeled oxalic acid in oxalate-accumulating plants such as spinach seedlings (Spinacia oleracea) and the detached leaves of woodsorrel (Oxalis stricta and O. oregana), shamrock (Oxalis adenopylla), and begonia (Begonia evansiana). In O. oregana, conversion occurred equally well in the presence or absence of light. This relationship between l-ascorbic acid metabolism and oxalic acid formation must be given careful consideration in attempts to explain oxalic accumulation in plants. PMID:16659288

Genome Wide Analysis of Differentially Expressed Genes in HK-2 Cells, a Line of Human Kidney Epithelial Cells in Response to Oxalate

PubMed Central

Koul, Sweaty; Khandrika, Lakshmipathi; Meacham, Randall B.; Koul, Hari K.

2012-01-01

Nephrolithiasis is a multi-factorial disease which, in the majority of cases, involves the renal deposition of calcium oxalate. Oxalate is a metabolic end product excreted primarily by the kidney. Previous studies have shown that elevated levels of oxalate are detrimental to the renal epithelial cells; however, oxalate renal epithelial cell interactions are not completely understood. In this study, we utilized an unbiased approach of gene expression profiling using Affymetrix HG_U133_plus2 gene chips to understand the global gene expression changes in human renal epithelial cells [HK-2] after exposure to oxalate. We analyzed the expression of 47,000 transcripts and variants, including 38,500 well characterized human genes, in the HK2 cells after 4 hours and 24 hours of oxalate exposure. Gene expression was compared among replicates as per the Affymetrix statistical program. Gene expression among various groups was compared using various analytical tools, and differentially expressed genes were classified according to the Gene Ontology Functional Category. The results from this study show that oxalate exposure induces significant expression changes in many genes. We show for the first time that oxalate exposure induces as well as shuts off genes differentially. We found 750 up-regulated and 2276 down-regulated genes which have not been reported before. Our results also show that renal cells exposed to oxalate results in the regulation of genes that are associated with specific molecular function, biological processes, and other cellular components. In addition we have identified a set of 20 genes that is differentially regulated by oxalate irrespective of duration of exposure and may be useful in monitoring oxalate nephrotoxicity. Taken together our studies profile global gene expression changes and provide a unique insight into oxalate renal cell interactions and oxalate nephrotoxicity. PMID:23028475

Isolation and characterizations of oxalate-binding proteins in the kidney

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

Roop-ngam, Piyachat; Chaiyarit, Sakdithep; Pongsakul, Nutkridta

Highlights: Black-Right-Pointing-Pointer The first large-scale characterizations of oxalate-binding kidney proteins. Black-Right-Pointing-Pointer The recently developed oxalate-conjugated EAH Sepharose 4B beads were applied. Black-Right-Pointing-Pointer 38 forms of 26 unique oxalate-binding kidney proteins were identified. Black-Right-Pointing-Pointer 25/26 (96%) of identified proteins had 'L-x(3,5)-R-x(2)-[AGILPV]' domain. -- Abstract: Oxalate-binding proteins are thought to serve as potential modulators of kidney stone formation. However, only few oxalate-binding proteins have been identified from previous studies. Our present study, therefore, aimed for large-scale identification of oxalate-binding proteins in porcine kidney using an oxalate-affinity column containing oxalate-conjugated EAH Sepharose 4B beads for purification followed by two-dimensional gel electrophoresis (2-DE) tomore » resolve the recovered proteins. Comparing with those obtained from the controlled column containing uncoupled EAH-Sepharose 4B (to subtract the background of non-specific bindings), a total of 38 protein spots were defined as oxalate-binding proteins. These protein spots were successfully identified by quadrupole time-of-flight mass spectrometry (MS) and/or tandem MS (MS/MS) as 26 unique proteins, including several nuclear proteins, mitochondrial proteins, oxidative stress regulatory proteins, metabolic enzymes and others. Identification of oxalate-binding domain using the PRATT tool revealed 'L-x(3,5)-R-x(2)-[AGILPV]' as a functional domain responsible for oxalate-binding in 25 of 26 (96%) unique identified proteins. We report herein, for the first time, large-scale identification and characterizations of oxalate-binding proteins in the kidney. The presence of positively charged arginine residue in the middle of this functional domain suggested its significance for binding to the negatively charged oxalate. These data will enhance future stone research, particularly on stone modulators.« less

Microbial Community Transplant Results in Increased and Long-Term Oxalate Degradation

PubMed Central

Miller, Aaron W.; Oakeson, Kelly F.; Dale, Colin; Dearing, M. Denise

2016-01-01

Gut microbes are essential for the degradation of dietary oxalate, and this function may play a role in decreasing the incidence of kidney stones. However, many oxalate-degrading bacteria are susceptible to antibiotics and the use of oxalate-degrading probiotics has only led to an ephemeral reduction in urinary oxalate. The objective of the current study was to determine the efficacy of using whole-community microbial transplants from a wild mammalian herbivore, Neotoma albigula, to increase oxalate degradation over the long term in the laboratory rat, Rattus norvegicus. We quantified the change in total oxalate degradation in lab rats immediately after microbial transplants and at 2- and 9-month intervals following microbial transplants. Additionally, we tracked the fecal microbiota of the lab rats, with and without microbial transplants, using high-throughput Illumina sequencing of a hyper-variable region of the 16S rRNA gene. Microbial transplants resulted in a significant increase in oxalate degradation, an effect that persisted 9 months after the initial transplants. Functional persistence was corroborated by the transfer, and persistence of a group of bacteria previously correlated with oxalate consumption in N. albigula, including an anaerobic bacterium from the genus Oxalobacter known for its ability to use oxalate as a sole carbon source. The results of this study indicate that whole-community microbial transplants are an effective means for the persistent colonization of oxalate-degrading bacteria in the mammalian gut. PMID:27312892

Intestinal adaptations in chronic kidney disease and the influence of gastric bypass surgery.

PubMed

Hatch, Marguerite

2014-09-01

Studies have shown that compensatory adaptations in gastrointestinal oxalate transport can impact the amount of oxalate excreted by the kidney. Hyperoxaluria is a major risk factor in the formation of kidney stones, and oxalate is derived from both the diet and the liver metabolism of glyoxylate. Although the intestine generally absorbs oxalate from dietary sources and can contribute as much as 50% of urinary oxalate, enteric oxalate elimination plays a significant role when renal function is compromised. While the mechanistic basis for these changes in the direction of intestinal oxalate movements in chronic renal failure involves an upregulation of angiotensin II receptors in the large intestine, enteric secretion/excretion of oxalate can also occur by mechanisms that are independent of angiotensin II. Most notably, the commensal bacterium Oxalobacter sp. interacts with the host enterocyte and promotes the movement of oxalate from the blood into the lumen, resulting in the beneficial effect of significantly lowering urinary oxalate excretion. Changes in the passive permeability of the intestine, such as in steatorrhoea and following gastric bypass, also promote oxalate absorption and hyperoxaluria. In summary, this report highlights the two-way physiological signalling between the gut and the kidney, which may help to alleviate the consequences of certain kidney diseases. © 2014 The Author. Experimental Physiology © 2014 The Physiological Society.

Determination of Oxalate Content in Herbal Remedies and Dietary Supplements Based on Plant Extracts.

PubMed

Siener, Roswitha; López-Mesas, Montserrat; Valiente, Manuel; Blanco, Francisco

2016-02-01

Lifestyle, especially diet, is a prominent risk factor that affects the formation of calcium oxalate stones. Urinary oxalate excretion is directly related to the amount of oral intake and intestinal absorption rate of oxalate. This work evaluated the possibility of increasing oxalate ingestion, which could lead to secondary hyperoxaluria, associated with the intake of herbal remedies and dietary supplements containing plant extracts. A wide variety of 17 commercially available drugs and dietary supplements were analyzed using ion chromatography. The results showed remarkable differences in oxalate contents of the extracts. Total oxalate concentrations ranged from 0.03 to 2.2 mg/g in solid samples and from 0.005 to 0.073 mg/mL in liquid samples. The selected herbal remedies and dietary supplements containing plant extracts represent only a low risk for calcium oxalate stone formers, if the recommended daily dose is not exceeded.

A simple method for quantitating the propensity for calcium oxalate crystallization in urine

NASA Technical Reports Server (NTRS)

Wabner, C. L.; Pak, C. Y.

1991-01-01

To assess the propensity for spontaneous crystallization of calcium oxalate in urine, the permissible increment in oxalate is calculated. The previous method required visual observation of crystallization with the addition of oxalate, this warranted the need for a large volume of urine and a sacrifice in accuracy in defining differences between small incremental changes of added oxalate. Therefore, this method has been miniaturized and spontaneous crystallization is detected from the depletion of radioactive oxalate. The new "micro" method demonstrated a marked decrease (p < 0.001) in the permissible increment in oxalate in urine of stone formers versus normal subjects. Moreover, crystallization inhibitors added to urine, in vitro (heparin or diphosphonate) or in vivo (potassium citrate administration), substantially increased the permissible increment in oxalate. Thus, the "micro" method has proven reliable and accurate in discriminating stone forming from control urine and in distinguishing changes of inhibitory activity.

Literature review for oxalate oxidation processes and plutonium oxalate solubility

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

Nash, C. A.

2015-10-01

A literature review of oxalate oxidation processes finds that manganese(II)-catalyzed nitric acid oxidation of oxalate in precipitate filtrate is a viable and well-documented process. The process has been operated on the large scale at Savannah River in the past, including oxidation of 20 tons of oxalic acid in F-Canyon. Research data under a variety of conditions show the process to be robust. This process is recommended for oxalate destruction in H-Canyon in the upcoming program to produce feed for the MOX facility. Prevention of plutonium oxalate precipitation in filtrate can be achieved by concentrated nitric acid/ferric nitrate sequestration of oxalate.more » Organic complexants do not appear practical to sequester plutonium. Testing is proposed to confirm the literature and calculation findings of this review at projected operating conditions for the upcoming campaign.« less

Bifidobacterium animalis subsp. lactis decreases urinary oxalate excretion in a mouse model of primary hyperoxaluria

PubMed Central

Whittamore, Jonathan M.; Hatch, Marguerite

2015-01-01

Hyperoxaluria significantly increases the risk of calcium oxalate kidney stone formation. Since several bacteria have been shown to metabolize oxalate in vitro, including probiotic bifidobacteria, we focused on the efficiency and possible mechanisms by which bifidobacteria can infuence oxalate handling in vivo, especially in the intestines, and compared these results with the reported effects of Oxalobacter formigenes. Bifidobacterium animalis subsp. lactis DSM 10140 and B. adolescentis ATCC 15703 were administered to wild-type (WT) mice and to mice defcient in the hepatic enzyme alanine-glyoxylate aminotransferase (Agxt−/−, a mouse model of Primary Hyperoxaluria) that were fed an oxalate-supplemented diet. The administration of B. animalis subsp. lactis led to a significant decrease in urinary oxalate excretion in WT and Agxt−/− mice when compared to treatment with B. adolescent-is. Detection of B. animalis subsp. lactis in feces revealed that 3 weeks after oral gavage with the bacteria 64 % of WT mice, but only 37 % of Agxt−/− mice were colonized. Examining intestinal oxalate fuxes showed there were no significant changes to net oxalate secretion in colonized animals and were therefore not associated with the changes in urinary oxalate excretion. These results indicate that colonization with B. animalis subsp. lactis decreased urinary oxalate excretion by degrading dietary oxalate thus limiting its absorption across the intestine but it did not promote enteric oxalate excretion as reported for O. formigenes. Preventive or therapeutic administration of B. animalis subsp. lactis appears to have some potential to beneficially infuence dietary hyperoxaluria in mice. PMID:25269440

Pathology and Epidemiology of Oxalate Nephrosis in Cheetahs.

PubMed

Mitchell, Emily P; Church, Molly E; Nemser, Sarah M; Yakes, Betsy Jean; Evans, Eric R; Reimschuessel, Renate; Lemberger, Karin; Thompson, Peter N; Terio, Karen A

2017-11-01

To investigate cases of acute oxalate nephrosis without evidence of ethylene glycol exposure, archived data and tissues from cheetahs ( Acinonyx jubatus) from North America ( n = 297), southern Africa ( n = 257), and France ( n = 40) were evaluated. Renal and gastrointestinal tract lesions were characterized in a subset of animals with ( n = 100) and without ( n = 165) oxalate crystals at death. Crystals were confirmed as calcium oxalate by Raman spectroscopy in 45 of 47 cheetahs tested. Crystals were present in cheetahs from 3.7 months to 15.9 years old. Cheetahs younger than 1.5 years were less likely to have oxalates than older cheetahs ( P = .034), but young cheetahs with oxalates had more oxalate crystals than older cheetahs ( P < .001). Cheetahs with oxalate crystals were more likely to have renal amyloidosis, interstitial nephritis, or colitis and less likely to have glomerular loop thickening or gastritis than those without oxalates. Crystal number was positively associated with renal tubular necrosis ( P ≤ .001), regeneration ( P = .015), and casts ( P ≤ .001) but inversely associated with glomerulosclerosis, renal amyloidosis, and interstitial nephritis. Crystal number was unrelated to the presence or absence of colitis and was lower in southern African than American and European animals ( P = .01). This study found no evidence that coexisting chronic renal disease (amyloidosis, interstitial nephritis, or glomerulosclerosis), veno-occlusive disease, gastritis, or enterocolitis contributed significantly to oxalate nephrosis. Oxalate-related renal disease should be considered as a potential cause of acute renal failure, especially in young captive cheetahs. The role of location, diet, stress, and genetic predisposition in the pathogenesis of oxalate nephrosis in cheetahs warrants further study.

Artificial photosynthesis of oxalate and oxalate-based polymer by a photovoltaic reactor

PubMed Central

Nong, Guangzai; Chen, Shan; Xu, Yuanjin; Huang, Lijie; Zou, Qingsong; Li, Shiqiang; Mo, Haitao; Zhu, Pingchuan; Cen, Weijian; Wang, Shuangfei

2014-01-01

A photovoltaic reactor was designed for artificial photosynthesis, based on the reactions involved in high energy hydrogen atoms, which were produced from water electrolysis. Water and CO2, under the conditions studied, were converted to oxalate (H2C2O4) and a polymer. This was the first time that the oxalates and oxalate-based polymer were produced from the artificial photosynthesis process. PMID:24389750

Study on the Key Technology of High Purity Strontium Titanate Powder Synthesized from Oxalic Acid Co-sediment Precipitation

NASA Astrophysics Data System (ADS)

Bi, Xiaoguo; Dong, Yingnan; Li, Yingjie; Niu, Wei; Tang, Jian; Ding, Shuang; Li, Meiyang

2017-09-01

Oxalate coprecipitation is applied in this paper, high purity titanium tetrachloride, and after the purification of strontium chloride, match with a certain concentration of solution, oxalate and strontium chloride and titanium tetrachloride in 1.005:1.000 make strontium titanium mixture ratio, slowly under 60°C to join in oxalic acid solution, aging around 4 h, get oxygen titanium strontium oxalate (SrTiO(C2O4)2 • 4H2 ) precipitation, after washing, drying and other process made oxygen titanium strontium oxalate powder.

Efficacy of Mixtures of Magnesium, Citrate and Phytate as Calcium Oxalate Crystallization Inhibitors in Urine.

PubMed

Grases, Felix; Rodriguez, Adrian; Costa-Bauza, Antonia

2015-09-01

The main aim of the current study was to evaluate the effectiveness of mixtures of magnesium, citrate and phytate as calcium oxalate crystallization inhibitors. A turbidimetric assay in synthetic urine was performed to obtain induction times for calcium oxalate crystallization in the absence and presence of different mixtures of inhibitors. The morphology of calcium oxalate crystals in the absence or presence of inhibitors and mixtures of the inhibitors was evaluated in 2 crystallization experiments at low and high calcium oxalate supersaturation. The crystals formed were examined using scanning electron microscopy. Examination of crystallization induction times revealed clear inhibitory effects of magnesium, citrate and phytate on calcium oxalate crystallization, supporting usefulness in the treatment and prevention of calcium oxalate nephrolithiasis. Significant synergistic effects between magnesium and phytate were observed. Scanning electron microscopy images revealed that phytate is a powerful crystal growth inhibitor of calcium oxalate, totally preventing the formation of trihydrate and monohydrate. In addition to crystallization inhibition capacity, citrate and magnesium avoided calcium oxalate crystallization by decreasing its supersaturation. The synergistic effect between magnesium and phytate on calcium oxalate crystallization suggests that a combination of these 2 compounds may be highly useful as antilithiasis therapy. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Oxalate Content of Taro Leaves Grown in Central Vietnam.

PubMed

Du Thanh, Hang; Phan Vu, Hai; Vu Van, Hai; Le Duc, Ngoan; Le Minh, Tuan; Savage, Geoffrey

2017-01-01

Leaves were harvested from four different cultivars of Colocasia esculenta and three cultivars of Alocasia odora that were growing on nine different farms in central Vietnam. The total, soluble and insoluble oxalate contents of the leaves were extracted and measured using HPLC chromatography. Total calcium determinations were also carried out on the same samples. The total oxalate content of the leaves ranged from 433.8 to 856.1 mg/100 g wet matter (WM) while the soluble oxalate ranged from 147.8 to 339.7 mg/100 g WM. The proportion of soluble oxalate ranged from 28% to 41% (overall mean 35%) of the total oxalate content of the leaves. The equivalent insoluble oxalate proportion ranged from 59% to 72% of the total (overall mean 65%). There was little difference between the Colocasia esculenta and Alocasia odora taro cultivars, although the total oxalate content was significantly higher in Alocasia odora cultivars. The overall mean total calcium content was 279.5 mg/100 WM and the percentage of insoluble calcium bound as calcium oxalate ranged from 31.7% to 57.3% of the total calcium content (overall mean 47.1%). The oxalate content in taro leaves is a major factor to consider when different cultivars of taro are recommended for human or animal consumption.

Natural abiotic formation of oxalic acid in soils: results from aromatic model compounds and soil samples.

PubMed

Studenroth, Sabine; Huber, Stefan G; Kotte, Karsten; Schöler, Heinz F

2013-02-05

Oxalic acid is the smallest dicarboxylic acid and plays an important role in soil processes (e.g., mineral weathering and metal detoxification in plants). We have first proven its abiotic formation in soils and investigated natural abiotic degradation processes based on the oxidation of soil organic matter, enhanced by Fe(3+) and H(2)O(2) as hydroxyl radical suppliers. Experiments with the model compound catechol and further hydroxylated benzenes were performed to examine a common degradation pathway and to presume a general formation mechanism of oxalic acid. Two soil samples were tested for the release of oxalic acid and the potential effects of various soil parameters on oxalic acid formation. Additionally, the soil samples were treated with different soil sterilization methods to prove the oxalic acid formation under abiotic soil conditions. Different series of model experiments were conducted to determine a range of factors including Fe(3+), H(2)O(2), reaction time, pH, and chloride concentration on oxalic acid formation. Under certain conditions, catechol is degraded up to 65.6% to oxalic acid referring to carbon. In serial experiments with two soil samples, oxalic acid was produced, and the obtained results are suggestive of an abiotic degradation process. In conclusion, Fenton-like conditions with low Fe(3+) concentrations and an excess of H(2)O(2) as well as acidic conditions were required for an optimal oxalic acid formation. The presence of chloride reduced oxalic acid formation.

A semi-micromethod for determination of oxalate in human plasma.

PubMed

Porowski, Tadeusz; Gałasiński, Władysław

2003-01-01

An enzymatic semi-micromethod for oxalate determination in human plasma was elaborated. The principle of the method depends on the oxalate isolation from deproteinized plasma, following determination by the calorimetric oxalate oxidase-peroxidase-indamine system. This method protects against internal oxalate losses and excludes an interference of contaminations. Results, obtained by this method, were reliable and ideally suited for use as real normal values (less than or equal to 6 microM) of oxalate content in the plasma of healthy individuals. The elaborated method, which can assay plasma oxalate accurately in normal individuals as well as in hyperoxalemic conditions is superior to those previously used. The procedure of semi-micromethod does not require expensive equipments and apparatus: it is simple and easy to perform in every laboratory and takes little time.

Ascorbate increases human oxaluria and kidney stone risk.

PubMed

Massey, Linda K; Liebman, Michael; Kynast-Gales, Susan A

2005-07-01

Currently, the recommended upper limit for ascorbic acid (AA) intake is 2000 mg/d. However, because AA is endogenously converted to oxalate and appears to increase the absorption of dietary oxalate, supplementation may increase the risk of kidney stones. The effect of AA supplementation on urinary oxalate was studied in a randomized, crossover, controlled design in which subjects consumed a controlled diet in a university metabolic unit. Stoneformers (n = 29; SF) and age- and gender-matched non-stoneformers (n = 19; NSF) consumed 1000 mg AA twice each day with each morning and evening meal for 6 d (treatment A), and no AA for 6 d (treatment N) in random order. After 5 d of adaptation to a low-oxalate diet, participants lived for 24 h in a metabolic unit, during which they were given 136 mg oxalate, including 18 mg 13C2 oxalic acid, 2 h before breakfast; they then consumed a controlled very low-oxalate diet for 24 h. Of the 48 participants, 19 (12 stoneformers, 7 non-stoneformers) were identified as responders, defined by an increase in 24-h total oxalate excretion > 10% after treatment A compared with N. Responders had a greater 24-h Tiselius Risk Index (TRI) with AA supplementation (1.10 +/- 0.66 treatment A vs. 0.76 +/- 0.42 treatment N) because of a 31% increase in the percentage of oxalate absorption (10.5 +/- 3.2% treatment A vs. 8.0 +/- 2.4% treatment N) and a 39% increase in endogenous oxalate synthesis with treatment A than during treatment N (544 +/- 131 A vs. 391 +/- 71 micromol/d N). The 1000 mg AA twice each day increased urinary oxalate and TRI for calcium oxalate kidney stones in 40% of participants, both stoneformers and non-stoneformers.

Reduced active transcellular intestinal oxalate secretion contributes to the pathogenesis of obesity-associated hyperoxaluria.

PubMed

Amin, Ruhul; Asplin, John; Jung, Daniel; Bashir, Mohamed; Alshaikh, Altayeb; Ratakonda, Sireesha; Sharma, Sapna; Jeon, Sohee; Granja, Ignacio; Matern, Dietrich; Hassan, Hatim

2018-05-01

Most kidney stones are composed of calcium oxalate, and minor changes in urine oxalate affect the stone risk. Obesity is a risk factor for kidney stones and a positive correlation of unknown etiology between increased body size, and elevated urinary oxalate excretion has been reported. Here, we used obese ob/ob (ob) mice to elucidate the pathogenesis of obesity-associated hyperoxaluria. These ob mice have significant hyperoxaluria (3.3-fold) compared with control mice, which is not due to overeating as shown by pair-feeding studies. Dietary oxalate removal greatly ameliorated this hyperoxaluria, confirming that it is largely enteric in origin. Transporter SLC26A6 (A6) plays an essential role in active transcellular intestinal oxalate secretion, and ob mice have significantly reduced jejunal A6 mRNA (- 80%) and total protein (- 62%) expression. While net oxalate secretion was observed in control jejunal tissues mounted in Ussing chambers, net absorption was seen in ob tissues, due to significantly reduced secretion. We hypothesized that the obesity-associated increase in intestinal and systemic inflammation, as reflected by elevated proinflammatory cytokines, suppresses A6-mediated intestinal oxalate secretion and contributes to obesity-associated hyperoxaluria. Indeed, proinflammatory cytokines (elevated in ob mice) significantly decreased intestinal oxalate transport in vitro by reducing A6 mRNA and total protein expression. Proinflammatory cytokines also significantly reduced active mouse jejunal oxalate secretion, converting oxalate transport from net secretion in vehicle-treated tissues to net absorption in proinflammatory cytokines-treated tissues. Thus, reduced active intestinal oxalate secretion, likely secondary to local and systemic inflammation, contributes to the pathogenesis of obesity-associated hyperoxaluria. Hence, proinflammatory cytokines represent potential therapeutic targets. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Protection of Metal Artifacts with the Formation of Metal–Oxalates Complexes by Beauveria bassiana

PubMed Central

Joseph, Edith; Cario, Sylvie; Simon, Anaële; Wörle, Marie; Mazzeo, Rocco; Junier, Pilar; Job, Daniel

2012-01-01

Several fungi present high tolerance to toxic metals and some are able to transform metals into metal–oxalate complexes. In this study, the ability of Beauveria bassiana to produce copper oxalates was evaluated. Growth performance was tested on various copper-containing media. B. bassiana proved highly resistant to copper, tolerating concentrations of up to 20 g L−1, and precipitating copper oxalates on all media tested. Chromatographic analyses showed that this species produced oxalic acid as sole metal chelator. The production of metal–oxalates can be used in the restoration and conservation of archeological and modern metal artifacts. The production of copper oxalates was confirmed directly using metallic pieces (both archeological and modern). The conversion of corrosion products into copper oxalates was demonstrated as well. In order to assess whether the capability of B. bassiana to produce metal–oxalates could be applied to other metals, iron and silver were tested as well. Iron appears to be directly sequestered in the wall of the fungal hyphae forming oxalates. However, the formation of a homogeneous layer on the object is not yet optimal. On silver, a co-precipitation of copper and silver oxalates occurred. As this greenish patina would not be acceptable on silver objects, silver reduction was explored as a tarnishing remediation. First experiments showed the transformation of silver nitrate into nanoparticles of elemental silver by an unknown extracellular mechanism. The production of copper oxalates is immediately applicable for the conservation of copper-based artifacts. For iron and silver this is not yet the case. However, the vast ability of B. bassiana to transform toxic metals using different immobilization mechanisms seems to offer considerable possibilities for industrial applications, such as the bioremediation of contaminated soils or the green synthesis of chemicals. PMID:22291684

Photoreduction of mercury metal (Hg) using catalyst of oxalic acid from cellulose of rice husks (Oryza sativa L.)

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

Sumiardi, Ade, E-mail: zulfasalmasaodah@gmail.com; Novi, Cory; Sukaesih, Esih

Photoreduction of mercury metal using catalyst of oxalic acid from cellulose of rice husks (Oryza sativa L.) is one of methods to reduce toxicity properties of the mercury metal in the society. The purpose of this research is to enhance photoreduction of mercury metal using catalyst of oxalic acid from cellulose of rice husks (Oryza sativa L.) at various concentrations. Photoreduction process is carried out in a closed reactor equipped with UV light and magnetic stirrer. Analysis of the influence of oxalic acid is determined by adding 25 mL of Hg (II) 5 ppm without oxalic acid, 25 mL of Hg (II) 5 ppmmore » + 25 mL of oxalic acid 3 ppm, 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 6 ppm, 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 9 ppm, 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 12 ppm and 25 mL of Hg (II) 5 ppm + 25 mL of oxalic acid 15 ppm. All treatments are followed by centrifugation for 15 minutes, then the concentration of Hg residual in the solution is measured by mercury analyzer. The research results showed that addition of oxalic acid concentration from the cellulose of rice husks (Oryza sativa L.) can enhance photoreduction of mercury metal. Optimum concentration reduction of mercury metal with addition of oxalic acid is obtained as many as 9-12 ppm. It can reduce the concentration of mercury metal (II) by 68.8% to 88.6%.« less

Cholinergic signaling inhibits oxalate transport by human intestinal T84 cells

PubMed Central

Cheng, Ming; Aronson, Peter S.

2012-01-01

Urolithiasis remains a very common disease in Western countries. Seventy to eighty percent of kidney stones are composed of calcium oxalate, and minor changes in urinary oxalate affect stone risk. Intestinal oxalate secretion mediated by anion exchanger SLC26A6 plays a major constitutive role in limiting net absorption of ingested oxalate, thereby preventing hyperoxaluria and calcium oxalate urolithiasis. Using the relatively selective PKC-δ inhibitor rottlerin, we had previously found that PKC-δ activation inhibits Slc26a6 activity in mouse duodenal tissue. To identify a model system to study physiologic agonists upstream of PKC-δ, we characterized the human intestinal cell line T84. Knockdown studies demonstrated that endogenous SLC26A6 mediates most of the oxalate transport by T84 cells. Cholinergic stimulation with carbachol modulates intestinal ion transport through signaling pathways including PKC activation. We therefore examined whether carbachol affects oxalate transport in T84 cells. We found that carbachol significantly inhibited oxalate transport by T84 cells, an effect blocked by rottlerin. Carbachol also led to significant translocation of PKC-δ from the cytosol to the membrane of T84 cells. Using pharmacological inhibitors, we observed that carbachol inhibits oxalate transport through the M3 muscarinic receptor and phospholipase C. Utilizing the Src inhibitor PP2 and phosphorylation studies, we found that the observed regulation downstream of PKC-δ is partially mediated by c-Src. Biotinylation studies revealed that carbachol inhibits oxalate transport by reducing SLC26A6 surface expression. We conclude that carbachol negatively regulates oxalate transport by reducing SLC26A6 surface expression in T84 cells through signaling pathways including the M3 muscarinic receptor, phospholipase C, PKC-δ, and c-Src. PMID:21956166

Oxalate modulates thiobarbituric acid reactive species (TBARS) production in supernatants of homogenates from rat brain, liver and kidney: effect of diphenyl diselenide and diphenyl ditelluride.

PubMed

Puntel, Robson Luiz; Roos, Daniel Henrique; Paixão, Márcio Weber; Braga, Antônio Luiz; Zeni, Gilson; Nogueira, Cristina Wayne; Rocha, Joao Batista Teixeira

2007-01-30

The aim of this paper was to investigate the mechanism(s) involved in the sodium oxalate pro-oxidative activity in vitro and the potential protection by diphenyl diselenide ((PhSe)(2)) and diphenyl ditelluride ((PhTe)(2)) using supernatants of homogenates from brain, liver and kidney. Oxalate causes a significant increase in the TBARS (thiobarbituric acid reactive species) production up to 4mmol/l and it had antioxidant activity from 8 to 16mmol/l in the brain and liver. Oxalate had no effect in kidney homogenates. The difference among tissues may be related to the formation of insoluble crystal of oxalate in kidney, but not in liver and brain homogenates. (PhSe)(2) and (PhTe)(2) reduced both basal and oxalate-induced TBARS in rat brain homogenates, whereas in liver homogenates they were antioxidant only on oxalate-induced TBARS production. (PhSe)(2) showed a modest effect on renal TBARS production, whereas (PhTe)(2) did not modulate TBARS in kidney preparations. Oxalate at 2mmol/l did not change deoxyribose degradation induced by Fe(2+) plus H(2)O(2), whereas at 20mmol/l it significantly prevents its degradation. Oxalate (up to 4mmol/l) did not alter iron (10micromol/l)-induced TBARS production in the brain preparations, whereas at 8mmol/l onwards it prevents iron effect. In liver preparations, oxalate amplifies iron pro-oxidant activity up to 4mmol/l, preventing iron-induced TBARS production at 16mmol/l onwards. These results support the antioxidant effect of organochalcogens against oxalate-induced TBARS production. In addition, our results suggest that oxalate pro- and antioxidant activity in vitro could be related to its interactions with iron ions.

Oxalate-Metabolising Genes of the White-Rot Fungus Dichomitus squalens Are Differentially Induced on Wood and at High Proton Concentration

PubMed Central

de Vries, Ronald P.; Timonen, Sari; Hildén, Kristiina

2014-01-01

Oxalic acid is a prevalent fungal metabolite with versatile roles in growth and nutrition, including degradation of plant biomass. However, the toxicity of oxalic acid makes regulation of its intra- and extracellular concentration crucial. To increase the knowledge of fungal oxalate metabolism, a transcriptional level study on oxalate-catabolising genes was performed with an effective lignin-degrading white-rot fungus Dichomitus squalens, which has demonstrated particular abilities in production and degradation of oxalic acid. The expression of oxalic-acid decomposing oxalate decarboxylase (ODC) and formic-acid decomposing formate dehydrogenase (FDH) encoding genes was followed during the growth of D. squalens on its natural spruce wood substrate. The effect of high proton concentration on the regulation of the oxalate-catabolising genes was determined after addition of organic acid (oxalic acid) and inorganic acid (hydrochloric acid) to the liquid cultures of D. squalens. In order to evaluate the co-expression of oxalate-catabolising and manganese peroxidase (MnP) encoding genes, the expression of one MnP encoding gene, mnp1, of D. squalens was also surveyed in the solid state and liquid cultures. Sequential action of ODC and FDH encoding genes was detected in the studied cultivations. The odc1, fdh2 and fdh3 genes of D. squalens showed constitutive expression, whereas ODC2 and FHD1 most likely are the main responsible enzymes for detoxification of high concentrations of oxalic and formic acids. The results also confirmed the central role of ODC1 when D. squalens grows on coniferous wood. Phylogenetic analysis revealed that fungal ODCs have evolved from at least two gene copies whereas FDHs have a single ancestral gene. As a conclusion, the multiplicity of oxalate-catabolising genes and their differential regulation on wood and in acid-amended cultures of D. squalens point to divergent physiological roles for the corresponding enzymes. PMID:24505339

The production of (14C) oxalate during the metabolism of (14C) carbohydrates in isolated rat hepatocytes.

PubMed

Rofe, A M; James, H M; Bais, R; Edwards, J B; Conyers, R A

1980-04-01

Oxalate (14C) was produced during the metabolism of (U-14C) carbohydrates in hepatocytes isolated from normal rats. At 10 mM, the order of oxalate production was fructose > glycerol > xylitol > sorbitol greater than or equal to glucose in the ratio 10 : 4 : 3 : 1 : 1. This difference between oxalate production from fructose and glucose was reflected in their rates of utilisation, glucose being poorly metabolised in hepatocytes from fasted rats. Fructose was rapidly metabolised, producing glucose, lactate and pyruvate as the major metabolites. Glycerol, xylitol and sorbitol were metabolised at half the rate of fructose, the major metabolites being glucose, lactate and glycerophosphate. The marked similarity in the pattern of intermediary metabolites produced by these polyols was not, however, reflected in the rates of oxalate production. Hepatic polyol metabolism resulted in high levels of cytosolic NADH, as indicated by elevated lactate : pyruvate and glycerophosphate : dihydroxyacetone phosphate ratios. The artificial electron acceptor, phenazine methosulphate (PMS) stimulated oxalate production from the polyols, particularly xylitol. In the presence of PMS, the order of oxalate production was fructose greater than or equal to xylitol > glycerol > sorbitol in the ratio 10 : 10 : 6 : 2. The production of glucose, lactate and pyruvate from the polyols was also stimulated by PMS, whereas the general metabolism of fructose, including oxalate production, was little affected. Oxalate (14C) was produced from (1-14C), (2-14C) and (6-14C) but not (3,4-14C) glucose in hepatocytes isolated from non-fasted, pyridoxine-deficient rats. Whilst this labelling pattern is consistent with oxalate being produced by a number of pathways, it is suggested that metabolism via hydroxypyruvate is a major route for oxalate production from various carbohydrates, with perhaps the exception of xylitol, which appears to have an alternative mechanism for oxalate production. The observation that carbohydrates, particularly fructose, contribute to endogenous oxalate production lends support to the hypothesis that a high sucrose consumption contributes to the formation of renal oxalate stones in man.

The Gastrointestinal Tract of the White-Throated Woodrat (Neotoma albigula) Harbors Distinct Consortia of Oxalate-Degrading Bacteria

PubMed Central

Kohl, Kevin D.; Dearing, M. Denise

2014-01-01

The microbiota inhabiting the mammalian gut is a functional organ that provides a number of services for the host. One factor that may regulate the composition and function of gut microbial communities is dietary toxins. Oxalate is a toxic plant secondary compound (PSC) produced in all major taxa of vascular plants and is consumed by a variety of animals. The mammalian herbivore Neotoma albigula is capable of consuming and degrading large quantities of dietary oxalate. We isolated and characterized oxalate-degrading bacteria from the gut contents of wild-caught animals and used high-throughput sequencing to determine the distribution of potential oxalate-degrading taxa along the gastrointestinal tract. Isolates spanned three genera: Lactobacillus, Clostridium, and Enterococcus. Over half of the isolates exhibited significant oxalate degradation in vitro, and all Lactobacillus isolates contained the oxc gene, one of the genes responsible for oxalate degradation. Although diverse potential oxalate-degrading genera were distributed throughout the gastrointestinal tract, they were most concentrated in the foregut, where dietary oxalate first enters the gastrointestinal tract. We hypothesize that unique environmental conditions present in each gut region provide diverse niches that select for particular functional taxa and communities. PMID:24362432

Reflectance spectroscopy of oxalate minerals and relevance to Solar System carbon inventories

NASA Astrophysics Data System (ADS)

Applin, Daniel M.; Izawa, Matthew R. M.; Cloutis, Edward A.

2016-11-01

The diversity of oxalate formation mechanisms suggests that significant concentrations of oxalic acid and oxalate minerals could be widely distributed in the Solar System. We have carried out a systematic study of the reflectance spectra of oxalate minerals and oxalic acid, covering the 0.2-16 μm wavelength region. Our analyses show that oxalates exhibit unique spectral features that enable discrimination between oxalate phases and from other commonly occurring compounds, including carbonates, in all regions of the spectrum except for the visible. Using these spectral data, we consider the possible contribution of oxalate minerals to previously observed reflectance spectra of many objects throughout the Solar System, including satellites, comets, and asteroids. We find that polycarboxylic acid dimers and their salts may explain the reflectance spectra of many carbonaceous asteroids in the 3 μm spectral region. We suggest surface concentration of these compounds may be a type of space weathering from the photochemical and oxidative decomposition of the organic macromolecular material found in carbonaceous chondrites. The stability and ubiquity of these minerals on Earth, in extraterrestrial materials, and in association with biological processes make them useful for many applications in Earth and planetary sciences.

Concentration gradient of oxalate from cortex to papilla in rat kidney.

PubMed

Nakatani, Tatsuya; Ishii, Keiichi; Sugimoto, Toshikado; Kamikawa, Sadanori; Yamamoto, Keisuke; Yoneda, Yukio; Kanazawa, Toshinao; Kishimoto, Taketoshi

2003-02-01

The kidney eliminates the major fraction of plasma oxalate. It is well known that oxalate is freely filtered by glomeruli and secreted by the proximal tubules. However, the renal handling of oxalate in distal nephrons, which is considered as playing an important role in stone formation, remains obscure. At 15-180 min after intravenous injection of 14C-oxalate to rats, the intrarenal localization of radioactivity was quantitatively measured by the radioluminographic method using a bioimaging analyzer. Tissue radioactivity was compared with plasma, and urinary radioactivities were measured by a liquid scintillation counter. The control study was conducted with 14C-inulin. The radioactivity of 14C-oxalate in the papilla was 10 times greater than in the cortex and eight times greater than in the medulla 180 min after injection when almost no radioactivity was present in the urine. In contrast, the radioactivity of 14C-inulin was nine times less in the papilla than in the cortex at the same time. Oxalate remains in the renal papilla for an extended period. This accumulation of oxalate may be attributed to calcium oxalate crystal fixation along the deep nephron which is considered to be the first step of stone formation.

Microbial growth on oxalate by a route not involving glyoxylate carboligase

PubMed Central

Blackmore, Maureen A.; Quayle, J. R.

1970-01-01

1. The metabolism of oxalate by the pink-pigmented organisms, Pseudomonas AM1, Pseudomonas AM2, Protaminobacter ruber and Pseudomonas extorquens has been compared with that of the non-pigmented Pseudomonas oxalaticus. 2. During growth on oxalate, all the organisms contain oxalyl-CoA decarboxylase, formate dehydrogenase and oxalyl-CoA reductase. This is consistent with oxidation of oxalate to carbon dioxide taking place via oxalyl-CoA, formyl-CoA and formate as intermediates, and also reduction of oxalate to glyoxylate taking place via oxalyl-CoA. 3. The pink-pigmented organisms, when grown on oxalate, contain l-serine–glyoxylate aminotransferase and hydroxypyruvate reductase but do not contain glyoxylate carboligase. The converse of this obtains in oxalate-grown Ps. oxalaticus. This indicates that, in contrast with Ps. oxalaticus, synthesis of C3 compounds from oxalate by the pink-pigmented organisms occurs by a variant of the `serine pathway' used by Pseudomonas AM1 during growth on C1 compounds. 4. Evidence in favour of this scheme is provided by the finding that a mutant of Pseudomonas AM1 that lacks hydroxypyruvate reductase is not able to grow on oxalate. PMID:5472155

High variability of the heterogeneous ice nucleation potential of oxalic acid dihydrate and sodium oxalate

NASA Astrophysics Data System (ADS)

Wagner, R.; Möhler, O.; Saathoff, H.; Schnaiter, M.; Leisner, T.

2010-04-01

The heterogeneous ice nucleation potential of airborne oxalic acid dihydrate and sodium oxalate particles in the deposition and condensation mode has been investigated by controlled expansion cooling cycles in the AIDA aerosol and cloud chamber of the Karlsruhe Institute of Technology at temperatures between 244 and 228 K. Previous laboratory studies have highlighted the particular role of oxalic acid dihydrate as the only species amongst a variety of other investigated dicarboxylic acids to be capable of acting as a heterogeneous ice nucleus in both the deposition and immersion mode. We could confirm a high deposition mode ice activity for 0.03 to 0.8 μm sized oxalic acid dihydrate particles that were either formed by nucleation from a gaseous oxalic acid/air mixture or by rapid crystallisation of highly supersaturated aqueous oxalic acid solution droplets. The critical saturation ratio with respect to ice required for deposition nucleation was found to be less than 1.1 and the size-dependent ice-active fraction of the aerosol population was in the range from 0.1 to 22%. In contrast, oxalic acid dihydrate particles that had crystallised from less supersaturated solution droplets and had been allowed to slowly grow in a supersaturated environment from still unfrozen oxalic acid solution droplets over a time period of several hours were found to be much poorer heterogeneous ice nuclei. We speculate that under these conditions a crystal surface structure with less-active sites for the initiation of ice nucleation was generated. Such particles partially proved to be almost ice-inactive in both the deposition and condensation mode. At times, the heterogeneous ice nucleation ability of oxalic acid dihydrate significantly changed when the particles had been processed in preceding cloud droplet activation steps. Such behaviour was also observed for the second investigated species, namely sodium oxalate. Our experiments address the atmospheric scenario that coating layers of oxalic acid or its salts may be formed by physical and chemical processing on pre-existing particulates such as mineral dust and soot. Given the broad diversity of the observed heterogeneous ice nucleability of the oxalate species, it is not straightforward to predict whether an oxalate coating layer will improve or reduce the ice nucleation ability of the seed aerosol particles.

High variability of the heterogeneous ice nucleation potential of oxalic acid dihydrate and sodium oxalate

NASA Astrophysics Data System (ADS)

Wagner, R.; Möhler, O.; Saathoff, H.; Schnaiter, M.; Leisner, T.

2010-08-01

The heterogeneous ice nucleation potential of airborne oxalic acid dihydrate and sodium oxalate particles in the deposition and condensation mode has been investigated by controlled expansion cooling cycles in the AIDA aerosol and cloud chamber of the Karlsruhe Institute of Technology at temperatures between 244 and 228 K. Previous laboratory studies have highlighted the particular role of oxalic acid dihydrate as the only species amongst a variety of other investigated dicarboxylic acids to be capable of acting as a heterogeneous ice nucleus in both the deposition and immersion mode. We could confirm a high deposition mode ice activity for 0.03 to 0.8 μm sized oxalic acid dihydrate particles that were either formed by nucleation from a gaseous oxalic acid/air mixture or by rapid crystallisation of highly supersaturated aqueous oxalic acid solution droplets. The critical saturation ratio with respect to ice required for deposition nucleation was found to be less than 1.1 and the size-dependent ice-active fraction of the aerosol population was in the range from 0.1 to 22%. In contrast, oxalic acid dihydrate particles that had crystallised from less supersaturated solution droplets and had been allowed to slowly grow in a supersaturated environment from still unfrozen oxalic acid solution droplets over a time period of several hours were found to be much poorer heterogeneous ice nuclei. We speculate that under these conditions a crystal surface structure with less-active sites for the initiation of ice nucleation was generated. Such particles partially proved to be almost ice-inactive in both the deposition and condensation mode. At times, the heterogeneous ice nucleation ability of oxalic acid dihydrate significantly changed when the particles had been processed in preceding cloud droplet activation steps. Such behaviour was also observed for the second investigated species, namely sodium oxalate. Our experiments address the atmospheric scenario that coating layers of oxalic acid or its salts may be formed by physical and chemical processing on pre-existing particulates such as mineral dust and soot. Given the broad diversity of the observed heterogeneous ice nucleability of the oxalate species, it is not straightforward to predict whether an oxalate coating layer will improve or reduce the ice nucleation ability of the seed aerosol particles.

(S)-citalopram influences amygdala modulation in healthy subjects: a randomized placebo-controlled double-blind fMRI study using dynamic causal modeling.

PubMed

Sladky, Ronald; Spies, Marie; Hoffmann, Andre; Kranz, Georg; Hummer, Allan; Gryglewski, Gregor; Lanzenberger, Rupert; Windischberger, Christian; Kasper, Siegfried

2015-03-01

Citalopram and Escitalopram are gold standard pharmaceutical treatment options for affective, anxiety, and other psychiatric disorders. However, their neurophysiologic function on cortico-limbic circuits is incompletely characterized. Here we studied the neuropharmacological influence of Citalopram and Escitalopram on cortico-limbic regulatory processes by assessing the effective connectivity between orbitofrontal cortex (OFC) and amygdala using dynamic causal modeling (DCM) applied to functional MRI data. We investigated a cohort of 15 healthy subjects in a randomized, crossover, double-blind design after 10days of Escitalopram (10mg/d (S)-citalopram), Citalopram (10mg/d (S)-citalopram and 10mg/d (R)-citalopram), or placebo. Subjects performed an emotional face discrimination task, while undergoing functional magnetic resonance imaging (fMRI) scanning at 3 Tesla. As hypothesized, the OFC, in the context of the emotional face discrimination task, exhibited a down-regulatory effect on amygdala activation. This modulatory effect was significantly increased by (S)-citalopram, but not (R)-citalopram. For the first time, this study shows that (1) the differential effects of the two enantiomers (S)- and (R)-citalopram on cortico-limbic connections can be demonstrated by modeling effective connectivity methods, and (2) one of their mechanisms can be linked to an increased inhibition of amygdala activation by the orbitofrontal cortex. Copyright © 2014 Elsevier Inc. All rights reserved.

How long should a trial of escitalopram treatment be in patients with major depressive disorder, generalised anxiety disorder or social anxiety disorder? An exploration of the randomised controlled trial database.

PubMed

Baldwin, David S; Stein, Dan J; Dolberg, Ornah T; Bandelow, Borwin

2009-06-01

To extend the knowledge of course of improvement in patients with major depressive disorder (MDD), social anxiety disorder (SAD) or generalised anxiety disorder (GAD) participating in randomised placebo-controlled trials (RCTs) and to infer the optimal duration of initial escitalopram treatment in clinical practice, after which intervention might be reasonable in case of non-response. Post hoc analysis of pooled clinical trial database for escitalopram in MDD (14 studies), GAD (4 studies) and SAD (2 studies). 'Onset' of action was defined as a 20% or more decrease from baseline score in disorder-specific psychopathological rating scales: 'response' as a 50% or more decrease from baseline score. In MDD, the probability of responding at week 8 if no onset was apparent at week 2 was 43%; in patients with an onset of effect the probability was nearly 80%. Similar patterns were observed in GAD and SAD. The chance of responding beyond week 4 in MDD, GAD and SAD was 20% or less if no effect had occurred by week 2. The pattern of response in these RCTs suggests that in patients with MDD, GAD or SAD in wider clinical practice, a period of at least 4 weeks is worthwhile before considering further intervention.

The safety of escitalopram during pregnancy and breastfeeding: a comprehensive review.

PubMed

Bellantuono, Cesario; Bozzi, Francesca; Orsolini, Laura; Catena-Dell'Osso, Mario

2012-11-01

Escitalopram (ESC) is considered one of the most effective selective serotonin reuptake inhibitors for the treatment of major depression. However, little is known on its potential risk of inducing major malformations (MMs) and perinatal complications (PCs). Hence, aim of the present study is to provide a comprehensive review of the available literature on the safety profile of ESC during pregnancy and breastfeeding. MEDLINE and PubMed databases were searched for English language articles by using the following keywords: escitalopram, selective serotonin reuptake inhibitors, major malformations, perinatal complications, pregnancy, and breastfeeding. Although some cases of MMs have been reported after maternal exposure to ESC during early pregnancy, the rate of these adverse events is substantially in the range of those reported in unexposed women. On the contrary, exposure to ESC seems to be significantly associated with some PCs. No adverse effects have been reported in the few studies evaluating its safety during breastfeeding. The available data seem to support the notion that ESC might be considered safe during pregnancy, in particular as far as MMs is concerned. However, similar to other selective serotonin reuptake inhibitors, it could be associated with an increased risk of PCs. Given the paucity of the studies published so far, no definitive conclusions can be drawn on its safety profile during breastfeeding. Copyright © 2012 John Wiley & Sons, Ltd.

Specific Inhibition of Hepatic Lactate Dehydrogenase Reduces Oxalate Production in Mouse Models of Primary Hyperoxaluria.

PubMed

Lai, Chengjung; Pursell, Natalie; Gierut, Jessica; Saxena, Utsav; Zhou, Wei; Dills, Michael; Diwanji, Rohan; Dutta, Chaitali; Koser, Martin; Nazef, Naim; Storr, Rachel; Kim, Boyoung; Martin-Higueras, Cristina; Salido, Eduardo; Wang, Weimin; Abrams, Marc; Dudek, Henryk; Brown, Bob D

2018-06-15

Primary hyperoxalurias (PHs) are autosomal recessive disorders caused by the overproduction of oxalate leading to calcium oxalate precipitation in the kidney and eventually to end-stage renal disease. One promising strategy to treat PHs is to reduce the hepatic production of oxalate through substrate reduction therapy by inhibiting liver-specific glycolate oxidase (GO), which controls the conversion of glycolate to glyoxylate, the proposed main precursor to oxalate. Alternatively, diminishing the amount of hepatic lactate dehydrogenase (LDH) expression, the proposed key enzyme responsible for converting glyoxylate to oxalate, should directly prevent the accumulation of oxalate in PH patients. Using RNAi, we provide the first in vivo evidence in mammals to support LDH as the key enzyme responsible for converting glyoxylate to oxalate. In addition, we demonstrate that reduction of hepatic LDH achieves efficient oxalate reduction and prevents calcium oxalate crystal deposition in genetically engineered mouse models of PH types 1 (PH1) and 2 (PH2), as well as in chemically induced PH mouse models. Repression of hepatic LDH in mice did not cause any acute elevation of circulating liver enzymes, lactate acidosis, or exertional myopathy, suggesting further evaluation of liver-specific inhibition of LDH as a potential approach for treating PH1 and PH2 is warranted. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Electrochemical synthesis and characterization of zinc oxalate nanoparticles

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

Shamsipur, Mojtaba, E-mail: mshamsipur@yahoo.com; Roushani, Mahmoud; Department of Chemistry, Ilam University, Ilam

2013-03-15

Highlights: ► Synthesis of zinc oxalate nanoparticles via electrolysis of a zinc plate anode in sodium oxalate solutions. ► Design of a Taguchi orthogonal array to identify the optimal experimental conditions. ► Controlling the size and shape of particles via applied voltage and oxalate concentration. ► Characterization of zinc oxalate nanoparticles by SEM, UV–vis, FT-IR and TG–DTA. - Abstract: A rapid, clean and simple electrodeposition method was designed for the synthesis of zinc oxalate nanoparticles. Zinc oxalate nanoparticles in different size and shapes were electrodeposited by electrolysis of a zinc plate anode in sodium oxalate aqueous solutions. It was foundmore » that the size and shape of the product could be tuned by electrolysis voltage, oxalate ion concentration, and stirring rate of electrolyte solution. A Taguchi orthogonal array design was designed to identify the optimal experimental conditions. The morphological characterization of the product was carried out by scanning electron microscopy. UV–vis and FT-IR spectroscopies were also used to characterize the electrodeposited nanoparticles. The TG–DTA studies of the nanoparticles indicated that the main thermal degradation occurs in two steps over a temperature range of 350–430 °C. In contrast to the existing methods, the present study describes a process which can be easily scaled up for the production of nano-sized zinc oxalate powder.« less

Codeine

MedlinePlus

... with other medications, to reduce coughing. Codeine will help relieve symptoms but will not treat the cause ... granisetron (Kytril), ondansetron (Zofran, Zuplenz), or palonosetron (Aloxi); selective serotonin-reuptake inhibitors such as citalopram (Celexa), escitalopram ( ...

Effect of different brewing times on soluble oxalate content of loose-packed black teas and tea bags.

PubMed

Mahdavi, Reza; Lotfi Yagin, Neda; Liebman, Michael; Nikniaz, Zeinab

2013-02-01

Because of the postulated role of increased dietary oxalate intake in calcium oxalate stone formation, the effect of different brewing times on soluble oxalate contents of loose-packed black tea and tea bags was studied. The oxalate content of 25 different samples of loose-packed black teas after brewing at 5, 10, 15, 30, and 60 min and of ten brands of tea bags after infusion for 1, 2, 3, 4, and 5 min was measured by enzymatic assay. The oxalate concentration resulting from different brewing times ranged from 4.3 to 6.2 mg/240 ml for loose-packed black teas and from 2.7 to 4.8 mg/240 ml for tea bags. There was a stepwise increase in oxalate concentration associated with increased brewing times.

Fish Oil Supplementation and Urinary Oxalate Excretion in Normal Subjects on a Low-oxalate Diet

PubMed Central

Lange, Jessica N.; Mufarrij, Patrick W.; Easter, Linda; Knight, John; Holmes, Ross P.; Assimos, Dean G.

2014-01-01

OBJECTIVE To determine if fish oil supplementation reduces endogenous oxalate synthesis in healthy subjects. MATERIALS AND METHODS Fifteen healthy non–stone-forming adults participated in this study. Subjects first abstained from using vitamins, medications, or foods enriched in omega-3 fatty acids for 30 days. Next, they collected two 24-hour urine specimens while consuming a self-selected diet. Subjects consumed an extremely low-oxalate and normal-calcium diet for 5 days and collected 24-hour urine specimens on the last 3 days of this diet. Next, the subjects took 2 fish oil capsules containing 650-mg eicosapentaenoic acid and 450-mg docosahexaenoic acid twice daily for 30 days. They consumed a self-selected diet on days 1–25 and the controlled diet on days 26–30. Twenty-four-hour urine samples were collected on days 28–30. Excretion levels of urinary analytes including oxalate and glycolate were analyzed. RESULTS Although there was a significant reduction in urinary oxalate, magnesium, and potassium excretions and an increase in uric acid excretion during the controlled dietary phases compared with the self-selected diet, there were no significant differences in their excretion during controlled diet phases with and without fish oil supplementation. CONCLUSION These results suggest that fish oil supplementation does not reduce endogenous oxalate synthesis or urinary oxalate excretion in normal adults during periods of extremely low oxalate intake. However, these results do not challenge the previously described reduction in urinary oxalate excretion demonstrated in normal subjects consuming a moderate amount of oxalate in conjunction with fish oil. PMID:25102784

Urinary oxalate to creatinine ratios in healthy Turkish schoolchildren.

PubMed

Dursun, Ismail; Çelik, İlknur; Poyrazoglu, Hakan M; Köse, Kader; Tanrıkulu, Esen; Sahin, Habibe; Yılmaz, Kenan; Öztürk, Ahmet; Yel, Sibel; Gündüz, Zübeyde; Düşünsel, Ruhan

2017-11-01

we aimed to establish reference values for urinary oxalate to creatinine ratios in healthy children aged 6-15 years and to investigate the relationship between their nutritional habits and oxalate excretion. Random urine specimens from 953 healthy children aged 6-15 years were obtained and analyzed for oxalate and creatinine. Additionally, a 24-h dietary recall form was prepared and given to them. The ingredient composition of the diet was calculated. The children were divided into three groups according to age: Group I (69 years, n = 353), Group II (10-12 years, n = 335), and Group III (13-15 years, n = 265). The 95th percentile of the oxalate to creatinine ratio for subjects aged 6-9, 10-12, and 13-15 years were 0.048, 0.042, and 0.042 mg/mg, respectively. The oxalate to creatinine ratio was significantly higher in Group 1 than in Group 2 and Group 3. Urinary oxalate excretion was positively correlated with increased protein intake and negatively correlated with age. A significant positive correlation was determined between urinary oxalate excretion and the proline, serine, protein, and glycine content of diet. Dietary proline intake showed a positive correlation with the urine oxalate to creatinine ratio and was found to be an independent predictor for urinary oxalate. These data lend support to the idea that every country should have its own normal reference values to determine the underlying metabolic risk factor for kidney stone disease since regional variation in the dietary intake of proteins and other nutrients can affect normal urinary excretion of oxalate.

Substituting milk for apple juice does not increase kidney stone risk in most normocalciuric adults who form calcium oxalate stones.

PubMed

Massey, L K; Kynast-Gales, S A

1998-03-01

Increasing intake of dietary calcium from less than 400 mg to 800 mg daily may decrease the absorption of dietary oxalate, which in turn would decrease urinary oxalate excretion. The effect of substituting milk for apple juice on urine composition and risk of calcium oxalate precipitability was studied. Twenty-one normocalciuric adults with a history of at least 1 calcium oxalate stone and urinary oxalate excretion exceeding 275 micromol/day on their self-selected diet. Randomized crossover trial. Each participant consumed two moderate-oxalate (2,011 micromol/day) study diets, which were identical except that one contained 360 mL milk and the other contained 540 mL apple juice as the beverage with meals. Four days free-living then 2 days in the metabolic unit of a university nutrition department. Tiselius risk index for calcium oxalate precipitability calculated from urine composition. Paired t tests. Twenty-four hour urinary oxalate excretion was 18% lower (P<.0001) on the milk diet vs the juice diet: 423 vs 514 micromol, respectively. Calcium excretion was 17% higher (P<.05) on the milk vs juice diet: 4.7 vs 3.9 mmol, respectively. Urinary magnesium and citrate excretion, volume, and Tiselius risk index did not differ between diets. Substituting 360 mL milk daily for apple juice with meals in a diet containing moderate amounts of dietary oxalate from whole grains, legumes, fruits, and vegetables does not increase the risk index of calcium oxalate precipitability in most normocalciuric adults who form stones.

40 CFR 721.10628 - Mixed metal oxalate (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Mixed metal oxalate (generic). 721... Substances § 721.10628 Mixed metal oxalate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as mixed metal oxalate (PMN P-12-432...

40 CFR 721.10628 - Mixed metal oxalate (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Mixed metal oxalate (generic). 721... Substances § 721.10628 Mixed metal oxalate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as mixed metal oxalate (PMN P-12-432...

Genomic evaluation of oxalate-degrading transgenic soybean in response to Sclerotinia sclerotiorum infection

USDA-ARS?s Scientific Manuscript database

Oxalate oxidases catalyze the degradation of oxalic acid (OA). Highly resistant transgenic soybean carrying an oxalate oxidase (OxO) gene and its susceptible parent soybean line, AC Colibri, were tested for genome-wide gene expression in response to the necrotrophic, OA producing pathogen Sclerotini...

Arthritis associated with calcium oxalate crystals in an anephric patient treated with peritoneal dialysis

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

Rosenthal, A.; Ryan, L.M.; McCarty, D.J.

1988-09-02

The authors report a case of calcium oxalate arthropathy in a woman undergoing intermittent peritoneal dialysis who was not receiving pharmacologic doses of ascorbic acid. She developed acute arthritis, with calcium oxalate crystals in Heberden's and Bouchard's nodes, a phenomenon previously described in gout. Intermittent peritoneal dialysis may be less efficient than hemodialysis in clearing oxalate, and physicians should now consider calcium oxalate-associated arthritis in patients undergoing peritoneal dialysis who are not receiving large doses of ascorbic acid.

Granisetron

MedlinePlus

... 5-HT3 receptor antagonists. It works by blocking serotonin, a natural substance in the body that causes ... Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate); phenobarbital; selective serotonin reuptake inhibitors (SSRIs) such as citalopram (Celexa), escitalopram ( ...

Gut microbiota and oxalate homeostasis

PubMed Central

2017-01-01

This perspective focuses on how the gut microbiota can impact urinary oxalate excretion in the context of hyperoxaluria, a major risk factor in kidney stone disease. In the genetic disease of Primary Hyperoxaluria Type 1 (PH1), an increased endogenous production of oxalate, due to a deficiency of the liver enzyme alanine-glyoxylate aminotransferase (AGT), results in hyperoxaluria and oxalate kidney stones. The constant elevation in urinary oxalate in PH1 patients ultimately leads to tissue deposition of oxalate, renal failure and death and the only known cure for PH1 is a liver or liver-kidney transplant. The potential impact of a probiotic/therapeutic approach may be clinically significant in PH1 and could also extend to a much larger population of idiopathic oxalate stone formers who comprise ~12% of Americans, individuals with enteric hyperoxaluria, and an emerging population of hyperoxaluric patients who have undergone bariatric surgery and develop kidney stone disease as a consequence. PMID:28217701

Gut microbiota and oxalate homeostasis.

PubMed

Hatch, Marguerite

2017-01-01

This perspective focuses on how the gut microbiota can impact urinary oxalate excretion in the context of hyperoxaluria, a major risk factor in kidney stone disease. In the genetic disease of Primary Hyperoxaluria Type 1 (PH1), an increased endogenous production of oxalate, due to a deficiency of the liver enzyme alanine-glyoxylate aminotransferase (AGT), results in hyperoxaluria and oxalate kidney stones. The constant elevation in urinary oxalate in PH1 patients ultimately leads to tissue deposition of oxalate, renal failure and death and the only known cure for PH1 is a liver or liver-kidney transplant. The potential impact of a probiotic/therapeutic approach may be clinically significant in PH1 and could also extend to a much larger population of idiopathic oxalate stone formers who comprise ~12% of Americans, individuals with enteric hyperoxaluria, and an emerging population of hyperoxaluric patients who have undergone bariatric surgery and develop kidney stone disease as a consequence.

Growth Conditions To Reduce Oxalic Acid Content of Spinach

NASA Technical Reports Server (NTRS)

Johnson-Rutzke, Corinne

2003-01-01

A controlled-environment agricultural (CEA) technique to increase the nutritive value of spinach has been developed. This technique makes it possible to reduce the concentration of oxalic acid in spinach leaves. It is desirable to reduce the oxalic acid content because oxalic acid acts as an anti-nutritive calcium-binding component. More than 30 years ago, an enzyme (an oxidase) that breaks down oxalic acid into CO2 and H2O2 was discovered and found to be naturally present in spinach leaves. However, nitrate, which can also be present because of the use of common nitratebased fertilizers, inactivates the enzyme. In the CEA technique, one cuts off the supply of nitrate and keeps the spinach plants cool while providing sufficient oxygen. This technique provides the precise environment that enables the enzyme to naturally break down oxalate. The result of application of this technique is that the oxalate content is reduced by 2/3 in one week.

An antagonist treatment in combination with tracer experiments revealed isocitrate pathway dominant to oxalate biosynthesis in Rumex obtusifolius L

USDA-ARS?s Scientific Manuscript database

Oxalate accumulates in leaves of certain plants such as Rumex species (Polygonaceae). Oxalate plays important roles in defense to predator, detoxification of metallic ions, and in hydroxyl peroxide formation upon wounding/senescence. However, biosynthetic pathways of soluble oxalate are largely unkn...

[Quantitative mineralogical analyzes of kidney stones and diagnosing metabolic disorders in female patients with calcium oxalate urolithiasis].

PubMed

Kustov, A V; Moryganov, M A; Strel'nikov, A I; Zhuravleva, N I; Airapetyan, A O

2016-02-01

To conduct a complex examination of female patients with calcium oxalate urolithiasis to detect metabolic disorders, leading to stone formation. The study was carried out using complex physical and chemical methods, including quantitative X-ray phase analysis of urinary stones, pH measurement, volumetry, urine and blood spectrophotometry. Quantitative mineralogical composition of stones, daily urine pH profile, daily urinary excretion of ions of calcium, magnesium, oxalate, phosphate, citrate and uric acid were determined in 20 female patients with calcium oxalate stones. We have shown that most of the stones comprised calcium oxalate monohydrate or mixtures of calcium oxalate dihydrate and hydroxyapatite. Among the identified abnormalities, the most frequent were hypocitraturia and hypercalciuria - 90 and 45%, respectively. Our findings revealed that the daily secretion of citrate and oxalate in patients older than 50 years was significantly lower than in younger patients. In conclusion, daily urinary citrate excretion should be measured in female patients with calcium oxalate stones. This is necessary both to determine the causes of stone formation, and to monitor the effectiveness of citrate therapy.

MitoTEMPO Prevents Oxalate Induced Injury in NRK-52E Cells via Inhibiting Mitochondrial Dysfunction and Modulating Oxidative Stress

PubMed Central

Yu, Xiao; Liu, Jihong

2017-01-01

As one of the major risks for urolithiasis, hyperoxaluria can be caused by genetic defect or dietary intake. And high oxalate induced renal epithelial cells injury is related to oxidative stress and mitochondrial dysfunction. Here, we investigated whether MitoTEMPO, a mitochondria-targeted antioxidant, could protect against oxalate mediated injury in NRK-52E cells via inhibiting mitochondrial dysfunction and modulating oxidative stress. MitoSOX Red was used to determine mitochondrial ROS (mtROS) production. Mitochondrial membrane potential (Δψm) and quantification of ATP synthesis were measured to evaluate mitochondrial function. The protein expression of Nox4, Nox2, and p22 was also detected to explore the effect of oxalate and MitoTEMPO on NADPH oxidase. Our results revealed that pretreatment with MitoTEMPO significantly inhibited oxalate induced lactate dehydrogenase (LDH) and malondialdehyde (MDA) release and decreased oxalate induced mtROS generation. Further, MitoTEMPO pretreatment restored disruption of Δψm and decreased ATP synthesis mediated by oxalate. In addition, MitoTEMPO altered the protein expression of Nox4 and p22 and decreased the protein expression of IL-6 and osteopontin (OPN) induced by oxalate. We concluded that MitoTEMPO may be a new candidate to protect against oxalate induced kidney injury as well as urolithiasis. PMID:28116040

Total, Soluble and Insoluble Oxalate Contents of Ripe Green and Golden Kiwifruit.

PubMed

Nguyễn, Hà Vũ Hồng; Savage, Geoffrey P

2013-03-05

Three bulk samples of two different cultivars of kiwifruit, green ( Actinidia deliciosa L . ) and golden ( Actinidia chinensis L . ) were bought ripe, ready to eat from a local market. The aim of the study was to determine the oxalate composition of each of the three fractions of kiwifruit, namely skin, pulp and seeds. The pulp consisted of 90.4% of the edible portion of the two cultivars while the skin and seeds made up a mean of 8.0% and 1.6% respectively. Total oxalate was extracted with 2.0 M HCL at 21 °C for 15 min and soluble oxalates extracted at 21 °C in water for 15 min from each fraction. The total and soluble oxalate compositions of each fraction were determined using ion exchange HPLC chromatography. The pulp of golden kiwifruit contained lower amounts of total oxalates (15.7 vs. 19.3 mg/100 g FW) and higher amounts of soluble oxalates (8.5 vs. 7.6 mg/100 g FW) when compared to the green cultivar. The skin of the green cultivar contained lower levels of insoluble oxalates (36.9 vs. 43.6 mg/100 g FW), while the seeds of the green cultivar contained higher levels of insoluble oxalates 106.7 vs. 84.7 mg/100 g FW.

Effect of Oxalic Acid Treatment on Sediment Arsenic Concentrations and Lability under Reducing Conditions

PubMed Central

Sun, Jing; Bostick, Benjamin C.; Mailloux, Brian J.; Ross, James M.; Chillrud, Steven N.

2016-01-01

Oxalic acid enhances arsenic (As) mobilization by dissolving As host minerals and competing for sorption sites. Oxalic acid amendments thus could potentially improve the efficiency of widely used pump-and-treat (P&T) remediation. This study investigates the effectiveness of oxalic acid on As mobilization from contaminated sediments with different As input sources and redox conditions, and examines whether residual sediment As after oxalic acid treatment can still be reductively mobilized. Batch extraction, column, and microcosm experiments were performed in the laboratory using sediments from the Dover Municipal Landfill and the Vineland Chemical Company Superfund sites. Oxalic acid mobilized As from both Dover and Vineland sediments, although the efficiency rates were different. The residual As in both Dover and Vineland sediments after oxalic acid treatment was less vulnerable to microbial reduction than before the treatment. Oxalic acid could thus improve the efficiency of P&T. X-ray absorption spectroscopy analysis indicated that the Vineland sediment samples still contained reactive Fe(III) minerals after oxalic acid treatment, and thus released more As into solution under reducing conditions than the Dover samples. Therefore, the efficacy of P&T must consider sediment Fe mineralogy when evaluating its overall potential for remediating groundwater As. PMID:26970042

Aspects of calcium oxalate crystallization: theory, in vitro studies, and in vivo implementation.

PubMed

Rodgers, A

1999-11-01

There are three main approaches to urolithiasis research: theory, basic science, and clinical implementation. Although each approach has yielded meaningful results, there does not appear to be complete synergy between them. This article examines these approaches as they pertain to urinary calcium oxalate crystallization processes. Theoretical calculations were performed to examine the role of oxalate concentration on calcium oxalate supersaturation. The effects of magnesium, citrate, and combinations thereof on calcium oxalate crystallization kinetics were examined in a mixed suspension, mixed product removal crystallizer. Finally, male volunteers were given supplements of calcium alone and binary combinations of calcium, magnesium, and citrate to investigate their effects on the urinary supersaturation of calcium oxalate. Calculations showed that oxalate is 23 times more potent than calcium in its effect on the supersaturation of calcium oxalate. In the in vitro experiments, magnesium and citrate reduced the growth and nucleation kinetics as well as the supersaturation. In combination, these two components were more effective than the individual components in reducing the growth rate and the supersaturation. All of the supplements favorably altered the kinetic and thermodynamic risk factors. Calcium was the most effective in reducing the urinary excretion of oxalate. Articulation of these three approaches is essential for the meaningful investigation and understanding of urolithiasis.

The role of intestinal oxalate transport in hyperoxaluria and the formation of kidney stones in animals and man

PubMed Central

Whittamore, Jonathan M.; Hatch, Marguerite

2016-01-01

The intestine exerts a considerable influence over urinary oxalate in two ways, through the absorption of dietary oxalate and by serving as an adaptive extra-renal pathway for elimination of this waste metabolite. Knowledge of the mechanisms responsible for oxalate absorption and secretion by the intestine therefore have significant implications for understanding the etiology of hyperoxaluria, as well as offering potential targets for future treatment strategies for calcium oxalate kidney stone disease. In this review, we present the recent developments and advances in this area over the past 10 years, and put to the test some of the new ideas that have emerged during this time, using human and mouse models. A key focus for our discussion are the membrane-bound anion exchangers, belonging to the SLC26 gene family, some of which have been shown to participate in transcellular oxalate absorption and secretion. This has offered the opportunity to not only examine the roles of these specific transporters, revealing their importance to oxalate homeostasis, but to also probe the relative contributions made by the active transcellular and passive paracellular components of oxalate transport across the intestine. We also discuss some of the various physiological stimuli and signaling pathways which have been suggested to participate in the adaptation and regulation of intestinal oxalate transport. Finally, we offer an update on research into Oxalobacter formigenes, alongside recent investigations of other oxalate-degrading gut bacteria, in both laboratory animals and humans. PMID:27913853

An Assessment of Engineered Calcium Oxalate Crystal Formation on Plant Growth and Development as a Step toward Evaluating Its Use to Enhance Plant Defense.

PubMed

Nakata, Paul A

2015-01-01

The establishment of new approaches to control chewing insects has been sought not only for direct use in reducing crop loss but also in managing resistance to the pesticides already in use. Engineered formation of calcium oxalate crystals is a potential strategy that could be developed to fulfill both these needs. As a step toward this development, this study investigates the effects of transforming a non-calcium oxalate crystal accumulating plant, Arabidopsis thaliana, into a crystal accumulating plant. Calcium oxalate crystal accumulating A. thaliana lines were generated by ectopic expression of a single bacterial gene encoding an oxalic acid biosynthetic enzyme. Biochemical and cellular studies suggested that the engineered A. thaliana lines formed crystals of calcium oxalate in a manner similar to naturally occurring crystal accumulating plants. The amount of calcium oxalate accumulated in leaves also reached levels similar to those measured in the leaves of Medicago truncatula in which the crystals are known to play a defensive role. Visual inspection of the different engineered lines, however, suggested a phenotypic consequence on plant growth and development with higher calcium oxalate concentrations. The restoration of a near wild-type plant phenotype through an enzymatic reduction of tissue oxalate supported this observation. Overall, this study is a first to provide initial insight into the potential consequences of engineering calcium oxalate crystal formation in non-crystal accumulating plants.

Characterization of metabolic network of oxalic acid biosynthesis through RNA seq data analysis of developing spikes of finger millet (Eleusine coracana): Deciphering the role of key genes involved in oxalate formation in relation to grain calcium accumulation.

PubMed

Akbar, Naved; Gupta, Supriya; Tiwari, Apoorv; Singh, K P; Kumar, Anil

2018-04-05

In the present study, we identified seven major genes of oxalic acid biosynthesis pathway (SGAT, GGAT, ICL, GLO, MHAR, APO and OXO) from developing spike transcriptome of finger millet using rice as a reference. Sequence alignment of identified genes showed high similarity with their respective homolog in rice except for OXO and GLO. Transcript abundance (FPKM) reflects the higher accumulation of identified genes in GP-1 (low calcium genotype) as compared to GP-45 (high calcium genotype) which was further confirmed by qRT-PCR analysis, indicating differential oxalate formation in both genotypes. Determination of oxalic acid and tartaric acid content in developing spikes explain that higher oxalic acid content in GP-1 however, tartaric acid content was more in GP-45. Higher calcium content in GP-45 and lower oxalate accumulation may be due to the diversion of more ascorbic acid into tartaric acid and may correspond to less formation of calcium oxalate. Our results suggest that more than one pathway for oxalic acid biosynthesis might be present in finger millet with probable predominance of ascorbate-tartarate pathway rather than glyoxalate-oxalate conversion. Thus, finger millet can be use as an excellent model system for understanding more specific role of nutrients-antinutrients interactions, as evident from the present study. Copyright © 2018 Elsevier B.V. All rights reserved.

Anion exchange pathways for Cl sup minus transport in rabbit renal microvillus membranes

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

Karniski, L.P.; Aronson, P.S.

1987-09-01

The authors evaluated the mechanisms of chloride transport in microvillus membrane vesicles isolated from the rabbit renal cortex. The presence of Cl-formate exchange was confirmed. Outward gradients of oxaloacetate, HCO{sub 3}, acetate, lactate, succinate, sulfate, and p-aminohippurate (PAH) stimulated the rate of Cl uptake minimally or not at all. However, an outward gradient of oxalate stimulated Cl uptake by 70%, and an outward Cl gradient induced uphill oxalate uptake, indicting Cl-oxalate exchange. Moreover, an outward formate gradient induced uphill oxalate uptake, indicating formate-oxalate exchange. Studies of inhibitor and substrate specificity indicated the probably operation of at least two separate anionmore » exchangers in mediating Cl transport. The Cl-formate exchanger accepted Cl and formate as substrates, had little or no affinity for oxalate, was sensitive to inhibition by furosemide, and was less sensitive to inhibition by 4,4{prime}-diisothiocyanostilbene-2,2{prime}-disulfonic acid (DIDS). The Cl (formate)-oxalate exchanger also accepted Cl and formate as substrates but had high affinity for oxalate, was highly sensitive to inhibition by DIDS, and was less sensitive to inhibition by furosemide. The Cl-formate exchanger was electroneutral, whereas the Cl (formate)-oxalate exchanger was electrogenic. They conclude that at least separate anion exchangers mediating Cl transport are present on the luminal membrane of the rabbit proximal tubule cell. These exchangers may play important roles in mediating transtubular Cl and oxalate transport in this nephron segment.« less

Evaluation of soluble oxalates content in infusions of different kinds of tea and coffee available on the Polish market.

PubMed

Rusinek, Elzbieta

2012-01-01

Tea and coffee are the potentially rich source of oxalic acid, which can act as a antinutrient. The aim of this study was to determine and evaluate the content of soluble oxalates in teas and coffees available on the Polish market. The green, red and black teas, and black natural ground and instant coffees were used for preparing the infusions. The manganometric method was used for the determination of the oxalates in the infusions. The mean oxalates content in the infusions from 3 g of black teas was 115.68 mg/100 cm3 and was higher as compared to red teas (101.91 mg/100 cm3) and green teas (87.64 mg/100 cm3). Disregarding the variety of analyzed teas, the largest oxalates content was in infusions of pure one-component tea--"Sir Roger" (164.82-174.22 mg/100 cm3), while the lowest oxalates content was noted in the tea containing the components from other plants ("Bio-Active" with grapefruit juice--reaching as low level as 39.00 mg/100 cm3). Instant coffees contained larger amount of oxalates than natural ground coffees. Irrespective of the kind of the tested coffees, the lowest oxalates content was found in the infusions from the following coffees: Tchibo Exclusive--19.62 mg/100 cm3, Gala ulubiona--37.32 mg/100 cm3, and Maxwell House--38.40 mg/100 cm3, while the highest oxalates content in instant coffee--Nescafe Espiro 51.80 mg/100 cm3. The results revealed a significant relation between phytochemical composition of analyzed teas and coffees and the level of soluble oxalates in infusions prepared from the tested products.

Urinary oxalate to creatinine ratios in healthy Turkish schoolchildren

PubMed Central

Dursun, Ismail; Çelik, İlknur; Poyrazoglu, Hakan M.; Tanrıkulu, Esen; Sahin, Habibe; Yılmaz, Kenan; Öztürk, Ahmet; Yel, Sibel; Gündüz, Zübeyde; Düşünsel, Ruhan

2017-01-01

Abstract Aim: we aimed to establish reference values for urinary oxalate to creatinine ratios in healthy children aged 6–15 years and to investigate the relationship between their nutritional habits and oxalate excretion. Materials and methods: Random urine specimens from 953 healthy children aged 6–15 years were obtained and analyzed for oxalate and creatinine. Additionally, a 24-h dietary recall form was prepared and given to them. The ingredient composition of the diet was calculated. The children were divided into three groups according to age: Group I (69 years, n = 353), Group II (10–12 years, n = 335), and Group III (13–15 years, n = 265). Results: The 95th percentile of the oxalate to creatinine ratio for subjects aged 6–9, 10–12, and 13–15 years were 0.048, 0.042, and 0.042 mg/mg, respectively. The oxalate to creatinine ratio was significantly higher in Group 1 than in Group 2 and Group 3. Urinary oxalate excretion was positively correlated with increased protein intake and negatively correlated with age. A significant positive correlation was determined between urinary oxalate excretion and the proline, serine, protein, and glycine content of diet. Dietary proline intake showed a positive correlation with the urine oxalate to creatinine ratio and was found to be an independent predictor for urinary oxalate. Conclusions: These data lend support to the idea that every country should have its own normal reference values to determine the underlying metabolic risk factor for kidney stone disease since regional variation in the dietary intake of proteins and other nutrients can affect normal urinary excretion of oxalate. PMID:27846788

Crystal growth methods dedicated to low solubility actinide oxalates

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

Tamain, C., E-mail: christelle.tamain@cea.fr; Arab-Chapelet, B.; Rivenet, M.

Two novel crystal growth syntheses dedicated to low solubility actinide-oxalate systems and adapted to glove box handling are described. These methods based on the use of precursors of either actinide metal or oxalic acid have been optimized on lanthanide systems (analogue of actinides(III)) and then assessed on real actinide systems. They allow the synthesis of several actinide oxalate single crystals, Am{sub 2}(C{sub 2}O{sub 4}){sub 3}(H{sub 2}O){sub 3}·xH{sub 2}O, Th(C{sub 2}O{sub 4}){sub 2}·6H{sub 2}O, M{sub 2+x}[Pu{sup IV}{sub 2−x}Pu{sup III}{sub x}(C{sub 2}O{sub 4}){sub 5}]·nH{sub 2}O and M{sub 1−x}[Pu{sup III}{sub 1−x}Pu{sup IV}{sub x}(C{sub 2}O{sub 4}){sub 2}·H{sub 2}O]·nH{sub 2}O. It is the first timemore » that these well-known compounds are formed by crystal growth methods, thus enabling direct structural studies on transuranic element systems and acquisition of basic data beyond deductions from isomorphic (or not) lanthanide compounds. Characterizations by X-ray diffraction, UV–visible solid spectroscopy, demonstrate the potentialities of these two crystal growth methods to obtain oxalate compounds. - Graphical abstract: Two new single crystal growth methods dedicated to actinide oxalate compounds. - Highlights: • Use of diester as oxalate precursor for crystal growth of actinide oxalates. • Use of actinide oxide as precursor for crystal growth of actinide oxalates. • Crystal growth of Pu(III) and Am(III) oxalates. • Crystal growth of mixed Pu(III)/Pu(IV) oxalates.« less

Hygroscopic properties of oxalic acid and atmospherically relevant oxalates

NASA Astrophysics Data System (ADS)

Ma, Qingxin; He, Hong; Liu, Chang

2013-04-01

Oxalic acid and oxalates represent an important fraction of atmospheric organic aerosols, however, little knowledge about the hygroscopic behavior of these particles is known. In this study, the hygroscopic behavior of oxalic acid and atmospherically relevant oxalates (H2C2O4, (NH4)2C2O4, CaC2O4, and FeC2O4) were studied by Raman spectrometry and vapor sorption analyzer. Under ambient relative humidity (RH) of 10-90%, oxalic acid and these oxalates hardly deliquesce and exhibit low hygroscopicity, however, transformation between anhydrous and hydrated particles was observed during the humidifying and dehumidifying processes. During the water adsorption process, conversion of anhydrous H2C2O4, (NH4)2C2O4, CaC2O4, and FeC2O4 to their hydrated particles (i.e., H2C2O4·2H2O, (NH4)2C2O4·H2O, CaC2O4·H2O, and FeC2O4·2H2O) occurred at about 20% RH, 55% RH, 10% RH, and 75% RH, respectively. Uptake of water on hydrated Ca-oxalate and Fe-oxalate particles can be described by a multilayer adsorption isotherm. During the dehumidifying process, dehydration of H2C2O4·2H2O and (NH4)2C2O4·H2O occurred at 5% RH while CaC2O4·H2O and FeC2O4·2H2O did not undergo dehydration. These results implied that hydrated particles represent the most stable state of oxalic acid and oxalates in the atmosphere. In addition, the assignments of Raman shift bands in the range of 1610-1650 cm-1 were discussed according to the hygroscopic behavior measurement results.

Oxalate metal complexes in aerosol particles: implications for the hygroscopicity of oxalate-containing particles

NASA Astrophysics Data System (ADS)

Furukawa, T.; Takahashi, Y.

2011-05-01

Atmospheric aerosols have both a direct and an indirect cooling effect that influences the radiative balance at the Earth's surface. It has been estimated that the degree of cooling is large enough to weaken the warming effect of carbon dioxide. Among the cooling factors, secondary organic aerosols (SOA) play an important role in the solar radiation balance in the troposphere as SOA can act as cloud condensation nuclei (CCN) and extend the lifespan of clouds because of their high hygroscopic and water soluble nature. Oxalic acid is an important component of SOA, and is produced via several formation pathways in the atmosphere. However, it is not certain whether oxalic acid exists as free oxalic acid or as metal oxalate complexes in aerosols, although there is a marked difference in their solubility in water and their hygroscopicity. We employed X-ray absorption fine structure spectroscopy to characterize the calcium (Ca) and zinc (Zn) in aerosols collected at Tsukuba in Japan. Size-fractionated aerosol samples were collected for this purpose using an impactor aerosol sampler. It was shown that 10-60% and 20-100% of the total Ca and Zn in the finer particles (<2.1 μm) were present as Ca and Zn oxalate complexes, respectively. Oxalic acid is hygroscopic and can thus increase the CCN activity of aerosol particles, while complexes with various polyvalent metal ions such as Ca and Zn are not hygroscopic, which cannot contribute to the increase of the CCN activity of aerosols. Based on the concentrations of noncomplexed and metal-complexed oxalate species, we found that most of the oxalic acid is present as metal oxalate complexes in the aerosols, suggesting that oxalic acid does not always increase the hygroscopicity of aerosols in the atmosphere. Similar results are expected for other dicarboxylic acids, such as malonic and succinic acids. Thus, it is advisable that the cooling effect of organic aerosols should be estimated by including the information on metal oxalate complexes and metal complexes with other dicarboxylic acids in aerosols.

Neurotoxic effects of carambola in rats: the role of oxalate.

PubMed

Chen, Chien-Liang; Chou, Kang-Ju; Wang, Jyh-Seng; Yeh, Jeng-Hsien; Fang, Hua-Chang; Chung, Hsiao-Min

2002-05-01

Carambola (star fruit) has been reported to contain neurotoxins that cause convulsions, hiccups, or death in uremic patients, and prolong barbiturate-induced sleeping time in rats. The constituent responsible for these effects remains uncertain. Carambola contains a large quantity of oxalate, which can induce depression of cerebral function and seizures. This study was conducted to investigate the role of oxalate in carambola toxicity in rats. The effects on barbiturate-induced sleeping time and death caused by intraperitoneal administration of carambola juice were observed in Sprague-Dawley rats. To obtain a dose-dependent response curve and evaluate the lethal dose, rats were treated with serial amounts of pure carambola juice diluted with normal saline in a volume of 1:1. To test the role of oxalate in the neurotoxic effect of carambola, either 5.33 g/kg carambola after oxalate removal or 5.33 g/kg of pure carambola juice diluted with normal saline were administered intraperitoneally, while the control group was given normal saline before pentobarbital injection. The effects of carambola and oxalate-removed carambola on barbiturate-induced sleeping time were compared with those of saline. To assess the lethal effect of oxalate in carambola, we gave rats chemical oxalate at comparable concentrations to the oxalate content of carambola. Carambola juice administration prolonged barbiturate-induced sleeping time in a dose-dependent manner. The sleeping time of rats that received normal saline and 1.33 g/kg, 2.67 g/kg, 5.33 g/kg, and 10.67 g/kg of carambola juice were 66 +/- 16.6, 93.7 +/- 13.4, 113.3 +/- 11.4, 117.5 +/- 29.0, and 172.5 +/- 38.8 minutes, respectively. The three higher-dose groups had longer sleeping times than controls (p < 0.05 or 0.005). This effect was eliminated after the removal of oxalate from carambola juice. Four of eight rats in the 10.67-g/kg group and all rats in the 21.33 g/kg and chemical oxalate groups died after seizure. Lethal doses of carambola juice were rendered harmless by the oxalate removal procedure. Oxalate is a main constituent of carambola neurotoxicity. This finding suggests that patients with carambola intoxication should be treated for oxalate toxicosis.

Determination of urine oxalate level in rats with renal calcium oxalate calculus by high-performance liquid chromatography.

PubMed

Cao, Qiu-shi; Ba, Yuan-ming; Luo, Jun-hua; Dai, Qi

2015-02-01

To establish a method of high-performance liquid chromatography (HPLC) for determining the urine oxalate levle in rats with renal calcium oxalate calculus. Totally 24 SPF Wistar healthy male rats were randomly divided into control group(n=12)and ethylene glycol (EG) group (n=12). Rats in EG group were administered intragastrically with 2% ammonium chloride (AC)2 ml/rat per day+1% ethylene glycol (EG), along with free access to drinking water.The control group was fed with deionized water, along with the intragastric administration of normal saline (1 ml per day). Twenty-eight days after modelling, the 24-hour urine samples were collected, and the urine oxalic acid levels were determined using HPLC and the results were compared with those of catalytic spectrophotometry using oxidation of methyl. During the HPLC, the samples were separated on Aglient 5TC-C18 (250×4.6 mm,5 Μm), eluted with mixture of methanol (0.1 mol/L) and ammonium acetate (15:85) at 1.2 ml/min, and detected at 314 nm, with the column temperature being 20 ℃. The standard curves of high and low concentrations of oxalic acid were y=5909.1x+378730, R² =0.9984 and y=7810.5x-16635, R² =0.9967,respectively. The lowest detectable concentration in this method was 5 Μg/ml. The linear high concentration range of oxalate stood at 62.50-2000.00 Μg/ml, and the linear low concentration range of oxalate stood at 6.25-100.00 Μg/ml. Its average recovery was 95.1%, and its within-day and day-to-day precisions were 3.4%-10.8% and 3.8%-9.4%. Both HPLC and catalytic spectrophotometry showed significantly higher urinary oxalic acid concentration and 24 h urine oxalate level in EG group compared with the control group [urinary oxalic acid concentration: (736.35 ± 254.52) Μg/ml vs.(51.56 ± 36.34) Μg/ml,(687.35 ± 234.53) Μg/ml vs.(50.24 ± 42.34) Μg/ml;24 h urine oxalate level: (11.23 ± 4.12)mg vs.(0.87 ± 0.45)mg,(9.89 ± 3.55)mg vs. (0.77 ± 0.65)mg; all P<0.01]. No statistically significant difference was observed in the results of urinary oxalate concentration and 24 h urine oxalate level between HPLC and potassium chromate oxidation of methyl red spectrophotometry (all P>0.05). HPLC is a simple, rapid, and precise method in detecting urine oxalate level in rats with renal calcium oxalate calculus, with high recovery rate.

When Medication Is Prescribed

MedlinePlus

... or combination of medications for the patient. Selective serotonin reuptake inhibitors (SSRIs): citalopram (brand name: Celexa) escitalopram ( ... brand names: Paxil, Pexeva) sertraline (brand name: Zoloft) Serotonin and norepinephrine reuptake inhibitors (SNRIs): venlafaxine (brand name: ...

Determining the Structure of Oxalate Anion Using Infrared and Raman Spectroscopy Coupled with Gaussian Calculations

ERIC Educational Resources Information Center

Peterson, Karen I.; Pullman, David P.

2016-01-01

A laboratory project for the upper-division physical chemistry laboratory is described, and it combines IR and Raman spectroscopies with Gaussian electronic structure calculations to determine the structure of the oxalate anion in solid alkali oxalates and in aqueous solution. The oxalate anion has two limiting structures whose vibrational spectra…

Synthesis of calcium oxalate crystals in culture medium irradiated with non-equilibrium atmospheric-pressure plasma

NASA Astrophysics Data System (ADS)

Kurake, Naoyuki; Tanaka, Hiromasa; Ishikawa, Kenji; Nakamura, Kae; Kajiyama, Hiroaki; Kikkawa, Fumitaka; Mizuno, Masaaki; Yamanishi, Yoko; Hori, Masaru

2016-09-01

Octahedral particulates several tens of microns in size were synthesized in a culture medium irradiated through contact with a plume of non-equilibrium atmospheric-pressure plasma (NEAPP). The particulates were identified in the crystalline phase as calcium oxalate dihydrate (COD). The original medium contained constituents such as NaCl, d-glucose, CaCl2, and NaHCO3 but not oxalate or oxalic acid. The oxalate was clearly synthesized and crystallized in the medium as thermodynamically unstable COD crystals after the NEAPP irradiation.

A randomized, double-blind study of the efficacy and tolerability of extended-release quetiapine fumarate (quetiapine XR) monotherapy in patients with major depressive disorder

PubMed Central

Wang, Gang; McIntyre, Alexander; Earley, Willie R; Raines, Shane R; Eriksson, Hans

2014-01-01

Objectives To evaluate the efficacy and tolerability of once-daily extended release quetiapine fumarate (quetiapine XR) monotherapy in patients with major depressive disorder (MDD). Patients and methods This was a 10-week (8-week active treatment/2-week post-treatment) randomized, double-blind, placebo- and active-controlled study (D1448C00004). Patients received quetiapine XR 150 mg/day, escitalopram 10 mg/day, or placebo; patients with an inadequate response (<20% improvement in Montgomery–Åsberg Depression Rating Scale [MADRS] total score) at week two received double-dose treatment. The primary end point was week eight change from randomization in MADRS total score. Secondary end points included MADRS response (≥50% improvement) and remission (score ≤8); Hamilton Rating Scale for Depression total and item 1; Hamilton Rating Scale for Anxiety total, psychic, and somatic; Clinical Global Impressions – Severity of Illness total; Pittsburgh Sleep Quality Index (PSQI) global; and Quality of Life Enjoyment and Satisfaction Questionnaire – Short Form percentage maximum total scores. Tolerability was assessed throughout. Results A total of 471 patients was randomized. No significant improvements in MADRS total score were observed at week eight (last observation carried forward) with either active treatment (quetiapine XR, −17.21 [P=0.174]; escitalopram, −16.73 [P=0.346]) versus placebo (−15.61). There were no significant differences in secondary end points versus placebo, with the exception of week-eight change in PSQI global score (quetiapine XR, −4.96 [P<0.01] versus placebo, −3.37). Mixed-model repeated-measures analysis of observed-case data suggested that the primary analysis may not be robust. Most commonly reported adverse events included dry mouth, somnolence, and dizziness for quetiapine XR, and headache and nausea for escitalopram. Conclusion In this study, neither quetiapine XR (150/300 mg/day) nor escitalopram (10/20 mg/day) showed significant separation from placebo. Both compounds have been shown previously to be effective in the treatment of MDD; possible reasons for this failed study are discussed. Quetiapine XR was generally well tolerated, with a profile similar to that reported previously. PMID:24511235

Cardiovascular risk with non-steroidal anti-inflammatory drugs: systematic review of population-based controlled observational studies.

PubMed

McGettigan, Patricia; Henry, David

2011-09-01

Randomised trials have highlighted the cardiovascular risks of non-steroidal anti-inflammatory drugs (NSAIDs) in high doses and sometimes atypical settings. Here, we provide estimates of the comparative risks with individual NSAIDs at typical doses in community settings. We performed a systematic review of community-based controlled observational studies. We conducted comprehensive literature searches, extracted adjusted relative risk (RR) estimates, and pooled the estimates for major cardiovascular events associated with use of individual NSAIDs, in different doses, and in populations with low and high background risks of cardiovascular events. We also compared individual drugs in pair-wise (within study) analyses, generating ratios of RRs (RRRs). Thirty case-control studies included 184,946 cardiovascular events, and 21 cohort studies described outcomes in >2.7 million exposed individuals. Of the extensively studied drugs (ten or more studies), the highest overall risks were seen with rofecoxib, 1.45 (95% CI 1.33, 1.59), and diclofenac, 1.40 (1.27, 1.55), and the lowest with ibuprofen, 1.18 (1.11, 1.25), and naproxen, 1.09 (1.02, 1.16). In a sub-set of studies, risk was elevated with low doses of rofecoxib, 1.37 (1.20, 1.57), celecoxib, 1.26 (1.09, 1.47), and diclofenac, 1.22 (1.12, 1.33), and rose in each case with higher doses. Ibuprofen risk was seen only with higher doses. Naproxen was risk-neutral at all doses. Of the less studied drugs etoricoxib, 2.05 (1.45, 2.88), etodolac, 1.55 (1.28, 1.87), and indomethacin, 1.30 (1.19, 1.41), had the highest risks. In pair-wise comparisons, etoricoxib had a higher RR than ibuprofen, RRR = 1.68 (99% CI 1.14, 2.49), and naproxen, RRR = 1.75 (1.16, 2.64); etodolac was not significantly different from naproxen and ibuprofen. Naproxen had a significantly lower risk than ibuprofen, RRR = 0.92 (0.87, 0.99). RR estimates were constant with different background risks for cardiovascular disease and rose early in the course of treatment. This review suggests that among widely used NSAIDs, naproxen and low-dose ibuprofen are least likely to increase cardiovascular risk. Diclofenac in doses available without prescription elevates risk. The data for etoricoxib were sparse, but in pair-wise comparisons this drug had a significantly higher RR than naproxen or ibuprofen. Indomethacin is an older, rather toxic drug, and the evidence on cardiovascular risk casts doubt on its continued clinical use. Please see later in the article for the Editors' Summary.

Escitalopram

MedlinePlus

... works by increasing the amount of serotonin, a natural substance in the brain that helps maintain mental ... that do not exist (hallucinating) fever, sweating, confusion, fast or ... the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting ...

Effect of animal and vegetable protein intake on oxalate excretion in idiopathic calcium stone disease.

PubMed

Marangella, M; Bianco, O; Martini, C; Petrarulo, M; Vitale, C; Linari, F

1989-04-01

Oxalate excretion was measured in healthy subjects and idiopathic calcium stone-formers on dietary regimens which differed in the type and amount of protein allowed; 24-h urine collections were obtained from 41 practising vegetarians and 40 normal persons on a free, mixed, "mediterranean" diet. Twenty idiopathic calcium stone-formers were also studied while on two low calcium, low oxalate diets which differed in that animal protein was high in one and restricted in the other. Vegetarians had higher urinary oxalate levels than controls and although the calcium levels were markedly lower, urinary saturation with calcium/oxalate was significantly higher. This mild hypercalciuria was interpreted as being secondary to both a higher intake and increased fractional intestinal absorption of oxalate. Changing calcium stone-formers from a high to a low animal protein intake produced a significant decrease in calcium excretion but there was no variation in urinary oxalate. As a result, the decrease in calcium oxalate saturation was only marginal and not significant. It was concluded that dietary animal protein has a minimal effect on oxalate excretion. Mild hyperoxaluria of idiopathic calcium stone disease is likely to be intestinal in origin. Calcium stone-formers should be advised to avoid an excess of animal protein but the risks of a vegetable-rich diet should also be borne in mind.

[Formation of oxalate in oxaliplatin injection diluted with infusion solutions].

PubMed

Eto, Seiji; Yamamoto, Kie; Shimazu, Kounosuke; Sugiura, Toshimune; Baba, Kaori; Sato, Ayaka; Goromaru, Takeshi; Hagiwara, Yoshiaki; Hara, Keiko; Shinohara, Yoshitake; Takahashi, Kojiro

2014-01-01

Oxaliplatin use can cause acute peripheral neuropathy characterized by sensory paresthesias, which are markedly exacerbated by exposure to cold temperatures, and is a dose-limiting factor in the treatment of colorectal cancer.Oxalate is eliminated in a series of nonenzymatic conversions of oxaliplatin in infusion solutions or biological fluids.Elimination of oxalate from oxaliplatin has been suggested as one of the reasons for the development of acute neuropathy.In this study, we developed a high-performance liquid chromatography(HPLC)-based method to detect oxalate formation, and investigated the time dependent formation of oxalate in oxaliplatin diluted with infusion solutions.The results obtained showed that the amount of oxalate in the solution corresponded to 1.6% of oxaliplatin 8 h after oxaliplatin dilution with a 5% glucose solution. On the other hand, oxalate formation from oxaliplatin diluted with a saline solution was ten-fold higher than that from oxaliplatin diluted with the 5% glucose solution.Most patients who were intravenously injected with oxaliplatin experienced venous pain.As a preventive measure against venous pain, dexamethasone was added to the oxaliplatin injection.We measured the amount of oxalate formed in the dexamethasone-containing oxaliplatin injection diluted with a 5% glucose solution.The amount of oxalate formed when dexamethasone was added did not differ significantly from that formed when dexamethasone was not added.Thus, there are no clinical problems associated with the stability of oxaliplatin solutions.

Contrasting calcium localization and speciation in leaves of Medicago trunculata mutant COD5 analyzed via synchrotron X-ray techniques

USDA-ARS?s Scientific Manuscript database

Oxalate-producing plants accumulate calcium oxalate crystals (CaOx(C)) in the range of 3-80%(w/w) of their dry weight, reducing calcium (Ca) bioavailability. The calcium oxalate deficient 5 (cod5) mutant of Medicago truncatula has been previously shown to contain similar Ca, but lower oxalate and Ca...

PREPARATION OF OXALATES OF METALS OF ATOMIC NUMBER GREATER THAN 88

DOEpatents

Duffield, R.B.

1959-02-01

A method is presented for the preparation of oxalates of metals of atomic number greater than 88. A solid peroxide of the heavy metal is contacted with an aqueous oxalic acid solution ai a temperature of about 50 C for a period of time sufficient to form the insoluble metal oxalate which is subsequentiy recovered as a pures crystalline compound.

Correlation between oxalic acid production and copper tolerance in Wolfiporia cocos

Treesearch

C. A. Clausen; Frederick Green; B. M. Woodward; J. W. Evans; R. C. DeGroot

2000-01-01

The increased interest in copper-based wood preservatives has hastened the need for understanding why some fungi are able to attack copper-treated wood. Due in part to accumulation of oxalic acid by brown-rot fungi and visualization of copper oxalate crystals in wood decayed by known copper-tolerant decay fungi, oxalic acid has been implicated in copper tolerance by...

Improving the two-step remediation process for CCA-treated wood. Part I, Evaluating oxalic acid extraction

Treesearch

Carol Clausen

2004-01-01

In this study, three possible improvements to a remediation process for chromated-copper-arsenate (CCA) treated wood were evaluated. The process involves two steps: oxalic acid extraction of wood fiber followed by bacterial culture with Bacillus licheniformis CC01. The three potential improvements to the oxalic acid extraction step were (1) reusing oxalic acid for...

Oxalate deposition on asbestos bodies.

PubMed

Ghio, Andrew J; Roggli, Victor L; Richards, Judy H; Crissman, Kay M; Stonehuerner, Jacqueline D; Piantadosi, Claude A

2003-08-01

We report on a deposition of oxalate crystals on ferruginous bodies after occupational exposure to asbestos demonstrated in 3 patients. We investigated the mechanism and possible significance of this deposition by testing the hypothesis that oxalate generated through nonenzymatic oxidation of ascorbate by asbestos-associated iron accounts for the deposition of the crystal on a ferruginous body. Crocidolite asbestos (1000 microg/mL) was incubated with 500 micromol H(2)O(2) and 500 micromol ascorbate for 24 hours at 22 degrees C. The dependence of oxalate generation on iron-catalyzed oxidant production was tested with the both the metal chelator deferoxamine and the radical scavenger dimethylthiourea. Incubation of crocidolite, H(2)O(2), and ascorbate in vitro generated approximately 42 nmol of oxalate in 24 hours. Oxalate generation was diminished significantly by the inclusion of either deferoxamine or dimethylthiourea in the reaction mixture. Incubation of asbestos bodies and uncoated fibers isolated from human lung with 500 micromol H(2)O(2) and 500 micromol ascorbate for 24 hours at 22 degrees C resulted in the generation of numerous oxalate crystals. We conclude that iron-catalyzed production of oxalate from ascorbate can account for the deposition of this crystal on ferruginous bodies.

Evaluation of Oxalic Acid Treatments against the Mite Varroa destructor and Secondary Effects on Honey Bees Apis mellifera

PubMed Central

Adjlane, Noureddine; Tarek, El-Ounass; Haddad, Nizar

2016-01-01

Background: The Varroa destructor varroasis is a very serious parasite of honeybee Apis mellifera. The objective of this study was to evaluate the effectiveness of Varroa treatment using organic acid (oxalic acid) in Algeria identifying its side effects on bee colonies. Methods: Treatment was conducted in one apiary consisting 30 colonies kept in Langstroth hives kind. Oxalic acid dripped directly on bees 5ml of this solution of oxalic acid per lane occupied by a syringe. Three doses were tested: 4.2, 3.2 and 2.1% oxalic acid is 100, 75 and 50 g of oxalic acid dehydrate in one litter of sugar syrup (1water to1 surge) concentration. Results: The percentage of average efficiency obtained for the first dose was 81%, 72.19% for the second dose, and 65% for third one, while the dose of 100 g oxalic acid causes a weakening of honey bee colonies. Conclusion: The experiments revealed that clear variation in the treatment efficiency among colonies that this might be related to brood presence therefore in order to assure the treatment efficiency oxalic acid should be part of a bigger strategy of Varroa treatment. PMID:28032102

Toxic and signalling effects of oxalic acid

PubMed Central

Lehner, Arnaud; Meimoun, Patrice; Errakhi, Rafik; Madiona, Karine; Barakate, Mustapha

2008-01-01

Oxalic acid is thought to be a key factor of the early pathogenic stage in a wide range of necrotrophic fungi. We have recently published that oxalic acid induces Programmed Cell Death (PCD) in Arabidopsis thaliana cells. This cell death results from an early anionic efflux which is a prerequisite for the synthesis of ethylene and the PCD. Complementary experiments have been carried out by using seedlings of A. thaliana. The effects of millimolar concentrations of oxalic acid were analysed on A. thaliana seedlings. A treatment with a 3 mM oxalic acid solution does not alter the development of the plants but induces the transcription of defence related genes which are anion channel dependant. Moreover, our results suggest that a pre-treatment of the seedlings with oxalic acid is able to confer the resistance of A. thaliana against Sclerotium rolfsii. Regarding our results, we suggest that oxalic acid plays two distinct roles, depending on the concentration: a high concentration of oxalic acid induces a large PCD and then contribute to the progression of the fungi. However, at low concentration it is able to induce the establishment of a resistance of the plant against the fungi. PMID:19704845

REVIEW OF ALTERNATIVE ENHANCED CHEMICAL CLEANING OPTIONS FOR SRS WASTE TANKS

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

Hay, M.; Koopman, D.

2009-08-01

A literature review was conducted to support the Task Technical and Quality Assurance Plan for Alternative Enhanced Chemical Cleaning (AECC) for sludge heel removal funded as part of the EM-21 Engineering and Technology program. The goal was to identify potential technologies or enhancements to the baseline oxalic acid cleaning process for chemically dissolving or mobilizing Savannah River Site (SRS) sludge heels. The issues with the potentially large volume of oxalate solids generated from the baseline process have driven an effort to find an improved or enhanced chemical cleaning technology for the tank heels. This literature review builds on a previousmore » review conducted in 2003. A team was charged with evaluating the information in these reviews and developing recommendations of alternative technologies to pursue. The new information in this report supports the conclusion of the previous review that oxalic acid remains the chemical cleaning agent of choice for dissolving the metal oxides and hydroxides found in sludge heels in carbon steel tanks. The potential negative impact of large volumes of sodium oxalate on downstream processes indicates that the amount of oxalic acid used for chemical cleaning needs to be minimized as much as possible or the oxalic acid must be destroyed prior to pH adjustment in the receipt tank. The most straightforward way of minimizing the volume of oxalic acid needed for chemical cleaning is through more effective mechanical cleaning. Using a mineral acid to adjust the pH of the sludge prior to adding oxalic acid may also help to minimize the volume of oxalic acid used in chemical cleaning. If minimization of oxalic acid proves insufficient in reducing the volume of oxalate salts, several methods were found that could be used for oxalic acid destruction. For some waste tank heels, another acid or even caustic treatment (or pretreatment) might be more appropriate than the baseline oxalic acid cleaning process. Caustic treatment of high aluminum sludge heels may be appropriate as a means of reducing oxalic acid usage. Reagents other than oxalic acid may also be needed for removing actinide elements from the tank heels. A systems engineering evaluation (SEE) was performed on the various alternative chemical cleaning reagents and organic oxidation technologies discussed in the literature review. The objective of the evaluation was to develop a short list of chemical cleaning reagents and oxalic acid destruction methods that should be the focus of further research and development. The results of the SEE found that eight of the thirteen organic oxidation technologies scored relatively close together. Six of the chemical cleaning reagents were also recommended for further investigation. Based on the results of the SEE and plan set out in the TTQAP the following broad areas are recommended for future study as part of the AECC task: (1) Basic Chemistry of Sludge Dissolution in Oxalic Acid: A better understanding of the variables effecting dissolution of sludge species is needed to efficiently remove sludge heels while minimizing the use of oxalic acid or other chemical reagents. Tests should investigate the effects of pH, acid concentration, phase ratios, temperature, and kinetics of the dissolution reactions of sludge components with oxalic acid, mineral acids, and combinations of oxalic/mineral acids. Real waste sludge samples should be characterized to obtain additional data on the mineral phases present in sludge heels. (2) Simulant Development Program: Current sludge simulants developed by other programs for use in waste processing tests, while compositionally similar to real sludge waste, generally have more hydrated forms of the major metal phases and dissolve more easily in acids. Better simulants containing the mineral phases identified by real waste characterization should be developed to test chemical cleaning methods. (3) Oxalic Acid Oxidation Technologies: The two Mn based oxidation methods that scored highly in the SEE should be studied to evaluate long term potential. One of the AOP's (UV/O{sub 3}/Solids Separator) is currently being implemented by the SRS liquid waste organization for use in tank heel chemical cleaning. (4) Corrosion Issues: A program will be needed to address potential corrosion issues from the use of low molarity mineral acids and mixtures of oxalic/mineral acids in the waste tanks for short durations. The addition of corrosion inhibitors to the acids to reduce corrosion rates should be investigated.« less

Production and degradation of oxalic acid by brown rot fungi

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

Espejo, E.; Agosin, E.

1991-07-01

Our results show that all of the brown rot fungi tested produce oxalic acid in liquid as well as in semisolid cultures. Gloeophyllum trabeum, which accumulates the lowest amount of oxalic acid during decay of pine holocellulose, showed the highest polysaccharide-depolymerizing activity. Semisolid cultures inoculated with this fungus rapidly converted {sup 14}C-labeled oxalic acid to CO{sub 2} during cellulose depolymerization. The other brown rot fungi also oxidized {sup 14}C-labeled oxalic acid, although less rapidly. In contrast, semisolid cultures inoculated with the white rot fungus Coriolus versicolor did not significantly catabolize the acid and did not depolymerize the holocellulose during decay.more » Semisolid cultures of G. trabeum amended with desferrioxamine, a specific iron-chelating agent, were unable to lower the degree of polymerization of cellulose or to oxidize {sup 14}C-labeled oxalic acid to the extent or at the rate that control cultures did. These results suggest that both iron and oxalic acid are involved in cellulose depolymerization by brown rot fungi.« less

(Di­methyl­phosphor­yl)methanaminium hydrogen oxalate–oxalic acid (2/1)

PubMed Central

Bialek, Sebastian; Clemens, Rebecca; Reiss, Guido J.

2014-01-01

The reaction of (di­methyl­phosphor­yl)methanamine (dpma) with oxalic acid in ethanol yielded the title solvated salt, C3H11NOP+·C2HO4 −·0.5C2H2O4. Its asymmetric unit consists of one dpmaH+ cation, one hydrogen oxalate anion and a half-mol­ecule of oxalic acid located around a twofold rotation axis. The H atom of the hydrogen oxalate anion is statistically disordered over two positions that are trans to each other. The hydrogen oxalate monoanion is not planar (bend angle ∼16°) whereas the oxalic acid molecule shows a significantly smaller bend angle (∼7°). In the crystal, the components are connected by strong O—H⋯O and much weaker N—H⋯O hydrogen bonds, leading to the formation of layers extending parallel to (001). The structure was refined from a racemically twinned crystal with twin components in an approximate 1:1 ratio. PMID:24765013

Effect of heat treatment on the structure of incorporated oxalate species and photoluminescent properties of porous alumina films formed in oxalic acid

NASA Astrophysics Data System (ADS)

Vrublevsky, I.; Jagminas, A.; Hemeltjen, S.; Goedel, W. A.

2008-09-01

The present work focuses on the use of IR spectroscopy and photoluminescence spectral measurements for studying the treatment temperature effect on the compositional and luminescent properties of oxalic acid alumina films. In line with the recent researches we have also found that heat treatment of porous alumina films formed in oxalic acid leads to considerable changes in their photoluminescence properties: upon annealing the intensity of photoluminescence (PL) increases reaching a maximum at the temperature of around 500 °C and then decreases. IR spectra of as-grown and heat-treated films have proved that PL emission in the anodic alumina films is related with the state of 'structural' oxalate species incorporated in the oxide lattice. These results allowed us to conclude that PL behavior of oxalic acid alumina films can be explained through the concept of variations in the bonding molecular orbitals of incorporated oxalate species including σ- and π-bonds.

Evidence for a cytoplasmic pathway of oxalate biosynthesis in Aspergillus niger

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

Kubicek, C.P.; Schreferl-Kunar, G.; Woehrer, W.

1988-03-01

Oxalate accumulation of up to 8 g/liter was induced in Aspergillus niger by shifting the pH from 6 to 8. This required the presence of P/sub i/ and a nitrogen source and was inhibited by the protein synthesis inhibitor cycloheximide. Exogenously added /sup 14/CO/sub 2/ was not incorporated into oxalate, but was incorporated into acetate and malate, thus indicating the biosynthesis of oxalate by hydrolytic cleavage of oxaloacetate. Inhibition of mitochondrial citrate metabolism by fluorocitrate did not significantly decrease the oxalate yield. The putative enzyme that was responsible for this oxaloacetate hydrolase (EC 3.7.1.1), which was induced de novo duringmore » the pH shift. Subcellular fractionation of oxalic acid-forming mycelia of A. niger showed that this enzyme is located in the cytoplasm of A. niger. The results are consistent with a cytoplasmic pathway of oxalate formation which does not involve the tricarboxylic acid cycle.« less

Alterations of thorium oxalate morphology by changing elementary precipitation conditions

NASA Astrophysics Data System (ADS)

Tyrpekl, V.; Beliš, M.; Wangle, T.; Vleugels, J.; Verwerft, M.

2017-09-01

Oxalates of actinide elements are widely used in research and industry mainly due to their low solubility in aqueous solution and easy conversion to oxide. Although thorium oxide is worldwide mostly produced by the oxalate precipitation and conversion route, the powder morphology obtained through this process is known to inhibit the packing and sintering step of the pellet production. The presented work investigates the effects of oxalate precipitation conditions on the final powder morphology. Among the precipitation conditions considered are: pH of the thorium feed solution, concentration, temperature and the order of addition (thorium solution in oxalic acid solution and vice versa) known as reverse/direct strike. Herein, we show that the morphology of the final oxalate depends significantly on the above mentioned precipitation parameters.

Altered brain concentrations of citalopram and escitalopram in P-glycoprotein deficient mice after acute and chronic treatment.

PubMed

Karlsson, Louise; Carlsson, Björn; Hiemke, Christoph; Ahlner, Johan; Bengtsson, Finn; Schmitt, Ulrich; Kugelberg, Fredrik C

2013-11-01

According to both in vitro and in vivo data P-glycoprotein (P-gp) may restrict the uptake of several antidepressants into the brain, thus contributing to the poor success rate of current antidepressant therapies. The therapeutic activity of citalopram resides in the S-enantiomer, whereas the R-enantiomer is practically devoid of serotonin reuptake potency. To date, no in vivo data are available that address whether the enantiomers of citalopram and its metabolites are substrates of P-gp. P-gp knockout (abcb1ab (-/-)) and wild-type (abcb1ab (+/+)) mice underwent acute (single-dose) and chronic (two daily doses for 10 days) treatment with citalopram (10mg/kg) or escitalopram (5mg/kg) Serum and brain samples were collected 1-6h after the first or last i.p. injection for subsequent drug analysis by an enantioselective HPLC method. In brain, 3-fold higher concentrations of S- and R-citalopram, and its metabolites, were found in abcb1ab (-/-) mice than in abcb1ab (+/+) mice after both acute and chronic citalopram treatments. After escitalopram treatment, the S-citalopram brain concentration was 3-5 times higher in the knockout mice than in controls. The results provide novel evidence that the enantiomers of citalopram are substrates of P-gp. Possible clinical and toxicological implications of this finding need to be further elucidated. Copyright © 2013 Elsevier B.V. and ECNP. All rights reserved.

Impact of Antidepressants on Cytokine Production of Depressed Patients in Vitro

PubMed Central

Munzer, Alexander; Sack, Ulrich; Mergl, Roland; Schönherr, Jeremias; Petersein, Charlotte; Bartsch, Stefanie; Kirkby, Kenneth C.; Bauer, Katrin; Himmerich, Hubertus

2013-01-01

The interplay between immune and nervous systems plays a pivotal role in the pathophysiology of depression. In depressive episodes, patients show increased production of pro-inflammatory cytokines such as interleukin (IL)-1β and tumor necrosis factor (TNF)-α. There is limited information on the effect of antidepressant drugs on cytokines, most studies report on a limited sample of cytokines and none have reported effects on IL-22. We systematically investigated the effect of three antidepressant drugs, citalopram, escitalopram and mirtazapine, on secretion of cytokines IL-1β, IL-2, IL-4, IL-6, IL-17, IL-22 and TNF-α in a whole blood assay in vitro, using murine anti-human CD3 monoclonal antibody OKT3, and 5C3 monoclonal antibody against CD40, to stimulate T and B cells respectively. Citalopram increased production of IL-1β, IL-6, TNF-α and IL-22. Mirtazapine increased IL-1β, TNF-α and IL-22. Escitalopram decreased IL-17 levels. The influence of antidepressants on IL-2 and IL-4 levels was not significant for all three drugs. Compared to escitalopram, citalopram led to higher levels of IL-1β, IL-6, IL-17 and IL-22; and mirtazapine to higher levels of IL-1β, IL-17, IL-22 and TNF-α. Mirtazapine and citalopram increased IL-22 production. The differing profile of cytokine production may relate to differences in therapeutic effects, risk of relapse and side effects. PMID:24257035

Short-term SSRI treatment normalises amygdala hyperactivity in depressed patients.

PubMed

Godlewska, B R; Norbury, R; Selvaraj, S; Cowen, P J; Harmer, C J

2012-12-01

Antidepressant drugs such as selective serotonin re-uptake inhibitors (SSRIs) remediate negative biases in emotional processing in depressed patients in both behavioural and neural outcome measures. However, it is not clear if these effects occur before, or as a consequence of, changes in clinical state. In the present study, we investigated the effects of short-term SSRI treatment in depressed patients on the neural response to fearful faces prior to clinical improvement in mood. Altogether, 42 unmedicated depressed patients received SSRI treatment (10 mg escitalopram daily) or placebo in a randomised, parallel-group design. The neural response to fearful and happy faces was measured on day 7 of treatment using functional magnetic resonance imaging. A group of healthy controls was imaged in the same way. Amygdala responses to fearful facial expressions were significantly greater in depressed patients compared to healthy controls. However, this response was normalised in patients receiving 7 days treatment with escitalopram. There was no significant difference in clinical depression ratings at 7 days between the escitalopram and placebo-treated patients. Our results suggest that short-term SSRI treatment in depressed patients remediates amygdala hyperactivity in response to negative emotional stimuli prior to clinical improvement in depressed mood. This supports the hypothesis that the clinical effects of antidepressant treatment may be mediated in part through early changes in emotional processing. Further studies will be needed to show if these early effects of antidepressant medication predict eventual clinical outcome.

The effect of combined treatment with risperidone and antidepressants on the MK-801-induced deficits in the social interaction test in rats.

PubMed

Kamińska, Katarzyna; Rogóż, Zofia

2015-12-01

Several clinical reports have suggested that augmentation of atypical antipsychotics' activity by antidepressants may efficiently improve the treatment of negative and some cognitive symptoms of schizophrenia. The aim of the present study was to investigate the effect of antidepressant mirtazapine or escitalopram and risperidone (an atypical antipsychotic), given separately or jointly, on the MK-801-induced deficits in the social interaction test in rats. Antidepressants and risperidone were given 60 and 30 min before the test, respectively. The social interaction of male Wistar rats was measured for 10 min, starting 4 h after MK-801 (0.1 mg/kg) administration. In the social interaction test, MK-801-induced deficits in the parameters studied, i.e. the number of episodes and the time of interactions. Risperidone at a higher dose (0.1 mg/kg) reversed that effect. Co-treatment with an ineffective dose of risperidone (0.01 mg/kg) and mirtazapine (2.5 or 5 mg/kg) or escitalopram only at a dose of 5 mg/kg (but not 2.5 and 10 mg/kg) abolished the deficits evoked by MK-801. The obtained results suggest that especially mirtazapine, and to a smaller degree escitalopram may enhance the antipsychotic-like effect of risperidone in the animal test modeling some negative symptoms of schizophrenia. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Sources and atmospheric processes impacting oxalate at a suburban coastal site in Hong Kong: Insights inferred from 1 year hourly measurements

NASA Astrophysics Data System (ADS)

Zhou, Yang; Huang, Xiaohui Hilda; Bian, Qijing; Griffith, Stephen M.; Louie, Peter K. K.; Yu, Jian Zhen

2015-09-01

Oxalic acid is one of the most abundant dicarboxylic acids in the atmosphere, receiving a great deal of attention due to its potential influence on cloud condensation nucleus activities. In this work, we report 10 months of hourly oxalate measurements in particulate matter of less than 2.5 µm in aerodynamic diameter (PM2.5) by a Monitor for Aerosols and Gases in ambient Air at a suburban coastal site in Hong Kong from April 2012 to February 2013. A total of more than 6000 sets of oxalate and inorganic ion data were obtained. The mean (±SD) oxalate concentration was 0.34 (±0.18) µg m-3, accounting for 2.8% of the total ion mass and 1.5% of the PM2.5 mass. Seasonal variation showed higher concentrations in fall and winter (0.54 and 0.36 µg m-3, respectively) and lower concentrations in spring and summer (~0.26 µg m-3). Different from the inorganic ions, a shallow dip in the oxalate concentration consistently occurred in the morning after sunrise (around 9:00 A.M.) throughout all seasons. Our analysis suggests that this was likely due to photolysis of oxalate-Fe (III) complex under sunlight. In summer, a small daytime peak was discernable for oxalate and nitrate. This characteristic, together with a more evident diurnal variation of O3, indicates comparatively more active photochemical oxidation in summer than other seasons. High correlations were observed between oxalate and non-sea-salt SO42- (NSS) (R2 = 0.63) and Ox (O3 + NO2) (R2 = 0.48), indicating significant commonality in their secondary formation. Positive matrix factorization analysis of oxalate and other real-time gas and particle-phase component data estimates that secondary formation processes, including secondary gas or aqueous oxidation processes (49%), oxidation processes of biomass burning emissions (37%), accounted for the majority of PM2.5 oxalate. A backward trajectories cluster analysis found that higher oxalate/NSS ratios were associated with low pollution samples under the influence of marine air masses while the ratios were lower in high pollution samples that were typically associated with continental air masses passing through areas of high anthropogenic emissions. Isolating the "low pollution marine" aerosols across the entire data set indicates that oxalate production increased in the summer compared to other seasons, suggesting either more active marine emissions of oxalate precursors or stronger photochemical processes in the summer.

Turning sunlight into stone: the oxalate-carbonate pathway in a tropical tree ecosystem

NASA Astrophysics Data System (ADS)

Cailleau, G.; Braissant, O.; Verrecchia, E. P.

2011-07-01

An African oxalogenic tree, the iroko tree (Milicia excelsa), has the property to enhance carbonate precipitation in tropical oxisols, where such accumulations are not expected due to the acidic conditions in these types of soils. This uncommon process is linked to the oxalate-carbonate pathway, which increases soil pH through oxalate oxidation. In order to investigate the oxalate-carbonate pathway in the iroko system, fluxes of matter have been identified, described, and evaluated from field to microscopic scales. In the first centimeters of the soil profile, decaying of the organic matter allows the release of whewellite crystals, mainly due to the action of termites and saprophytic fungi. In addition, a concomitant flux of carbonate formed in wood tissues contributes to the carbonate flux and is identified as a direct consequence of wood feeding by termites. Nevertheless, calcite biomineralization of the tree is not a consequence of in situ oxalate consumption, but rather related to the oxalate oxidation inside the upper part of the soil. The consequence of this oxidation is the presence of carbonate ions in the soil solution pumped through the roots, leading to preferential mineralization of the roots and the trunk base. An ideal scenario for the iroko biomineralization and soil carbonate accumulation starts with oxalatization: as the iroko tree grows, the organic matter flux to the soil constitutes the litter, and an oxalate pool is formed on the forest ground. Then, wood rotting agents (mainly termites, saprophytic fungi, and bacteria) release significant amounts of oxalate crystals from decaying plant tissues. In addition, some of these agents are themselves producers of oxalate (e.g. fungi). Both processes contribute to a soil pool of "available" oxalate crystals. Oxalate consumption by oxalotrophic bacteria can then start. Carbonate and calcium ions present in the soil solution represent the end products of the oxalate-carbonate pathway. The solution is pumped through the roots, leading to carbonate precipitation. The main pools of carbon are clearly identified as the organic matter (the tree and its organic products), the oxalate crystals, and the various carbonate features. A functional model based on field observations and diagenetic investigations with δ13C signatures of the various compartments involved in the local carbon cycle is proposed. It suggests that the iroko ecosystem can act as a long-term carbon sink, as long as the calcium source is related to non-carbonate rocks. Consequently, this carbon sink, driven by the oxalate carbonate pathway around an iroko tree, constitutes a true carbon trapping ecosystem as defined by ecological theory.

Turning sunlight into stone: the oxalate-carbonate pathway in a tropical tree ecosystem

NASA Astrophysics Data System (ADS)

Cailleau, G.; Braissant, O.; Verrecchia, E. P.

2011-02-01

An African oxalogenic tree, the iroko tree (Milicia excelsa), has the property to enhance carbonate precipitation in tropical oxisols, where such accumulations are not expected due to the theoretical acidic conditions of these soils. This uncommon process is linked to the oxalate-carbonate pathway, which increases soil pH through oxalate oxidation. In order to investigate the oxalate-carbonate pathway in the iroko system, fluxes of matter have been identified, described, and evaluated from field to microscopic scales. In the first centimeters of the soil profile, decaying of the organic matter allows the release of whewellite crystals, mainly due to the action of termites and saprophytic fungi. Regarding the carbonate flux, another direct consequence of wood feeding is a concomitant flux of carbonate formed in wood tissues, which is not consumed by termites. Nevertheless, calcite biomineralization of the tree is not a consequence of in situ oxalate consumption, but rather related to the oxalate oxidation inside the upper part of the soil. The consequence of this oxidation is the presence of carbonate ions in the soil solution pumped through the roots, leading to preferential mineralization of the roots and the trunk base. An ideal scenario for the iroko biomineralization and soil carbonate accumulation starts with oxalatization: as the iroko tree grows, the organic matter flux to the soil constitutes the litter. Therefore, an oxalate pool is formed on the forest ground. Then, wood rotting gents (mainly termites, fungi, and bacteria) release significant amounts of oxalate crystals from decaying plant tissues. In addition some of these gents are themselves producers of oxalate (fungi). Both processes contribute to a soil pool of "available" oxalate crystals. Oxalate consumption by oxalotrophic bacteria can start. Carbonate and calcium ions present in the soil solution represent the end products of the oxalate-carbonate pathway. The solution is pumped through the roots, leading to carbonate precipitation. The main pools of carbon are clearly identified as the organic matter (the tree and its organic products), the oxalate crystals, and the various carbonate features. A functional model based on field observations and diagenetic investigations with δ13C signatures of the various compartments involved in the local carbon cycle is proposed. It suggests that the iroko ecosystem can act as a long-term carbon sink, as long as the calcium source is related to non-carbonate rocks. Consequently, this carbon sink, driven by the oxalate carbonate pathway around an iroko tree, constitutes a true carbon trapping ecosystem as define by the ecological theory.

Enzymatic oxalic acid regulation correlated with wood degradation in four brown-rot fungi

Treesearch

Anne Christine Steenkjær Hastrup; Frederick Green III; Patricia K. Lebow; Bo Jensen

2012-01-01

Oxalic acid is a key component in the initiation of brown-rot decay and it has been suggested that it plays multiple roles during the degradation process. Oxalic acid is accumulated to varying degrees among brown-rot fungi; however, details on active regulation are scarce. The accumulation of oxalic acid was measured in this study from wood degraded by the four brown-...

Enzymatic mechanism of oxalate production in the TCA and glyoxylate pathways using various isolates of Antrodia radiculosa

Treesearch

K.M. Jenkins; S.V. Diehl; C.A. Clausen; F. Green

2011-01-01

Brown-rot fungi produce oxalate in large amounts; however, levels of accumulation and function vary by species. Copper-tolerant fungi, like Antrodia radiculosa, produce and accumulate high levels of oxalate in response to copper. Oxalate biosynthesis in copper-tolerant fungi has been linked to the glyoxylate and tricarboxylic acid (TCA) cycles. Within these two cycles...

Calcium Oxalate Urolithiasis: A Case of Missing Microbes?

PubMed

Batagello, Carlos Alfredo; Monga, Manoj; Miller, Aaron W

2018-05-29

Urinary stone disease (USD) has known associations with the gut microbiota. Approximately 80% of kidney stones contain oxalate as a primary constituent and diverse oxalate-degrading bacteria exist within the human gut that may protect against USD. While bacteriotherapy represents a promising strategy to eliminate oxalate and reduce the risk of USD, oxalate-degrading probiotics have had limited success. To identify limitations of oxalate-degrading probiotics and refine development of bacteriotherapies to prevent USD, we review the literature associated with the gut microbiota and USD. A literature search was performed to identify publications that examine the role of oxalate-degrading bacteria or the whole gut microbiota in oxalate metabolism and the pathophysiology of USD. We conducted a meta-analysis of studies that examined the association of the whole gut microbiota with USD. In addition, we evaluated the gut microbiota of healthy individuals and those with co-morbidities related to USD using publically available data from the American Gut Project (AGP). Studies on O. formigenes reveal that colonization by this species is not a good predictor of USD risk nor urinary oxalate excretion. The species of oxalate-degrading bacteria used in probiotics and duration of administration does not impact efficacy or persistence. Studies focused on the whole gut microbiota reveal broad shifts in the gut microbiota associated with USD and a diverse microbial network is associated with oxalate metabolism. AGP data analysis demonstrated a strong overlap in microbial genera depleted in diseased individuals among USD and co-morbidities. The associations between the gut microbiota and USD extend beyond individual functional microbial species. Common shifts in the gut microbiota may facilitate the onset of USD and/or co-morbidities. The successful development of bacteriotherapies to inhibit USD will need to incorporate strategies that target a broad diversity of bacteria rather than focus on few specialist species.

The Relationship between Serum Oxalic Acid, Central Hemodynamic Parameters and Colonization by Oxalobacter formigenes in Hemodialysis Patients

PubMed Central

Gulhan, Baris; Turkmen, Kultigin; Aydin, Merve; Gunay, Murat; Cıkman, Aytekin; Kara, Murat

2015-01-01

Background/Objective Elevated pulse wave velocity (PWV) and central aortic blood pressures are independent predictors of increased cardiovascular morbidity and mortality in hemodialysis (HD) patients. Oxalic acid is a uremic retention molecule that is extensively studied in the pathogenesis of calcium oxalate stones. Oxalobacter formigenes, a member of the colon microbiota, has important roles in oxalate homeostasis. Data regarding the colonization by and the exact role of O. formigenes in the pathogenesis of oxalic acid metabolism in HD patients are scant. Hence, we aimed to determine the relationship between fecal O. formigenes colonization, serum oxalic acid and hemodynamic parameters in HD patients with regard to the colo-reno-cardiac axis. Methods Fifty HD patients were enrolled in this study. PWV and central aortic systolic (cASBP) and diastolic blood pressures (cADBP) were measured with a Mobil-O-Graph (I.E.M. GmbH, Stolberg, Germany). Serum oxalic acid levels were assessed by ELISA, and fecal O. formigenes DNA levels were isolated and measured by real-time PCR. Results Isolation of fecal O. formigenes was found in only 2 HD patients. One of them had 113,609 copies/ml, the other one had 1,056 copies/ml. Serum oxalic acid levels were found to be positively correlated with PWV (r = 0.29, p = 0.03), cASBP (r = 0.33, p = 0.001) and cADBP (r = 0.42, p = 0.002) and negatively correlated with LDL (r = −0.30, p = 0.03). In multivariate linear regression analysis, PWV was independently predicted by oxalic acid, glucose and triglyceride. Conclusions This is the first study that demonstrates the absence of O. formigenes as well as a relation between serum oxalic acid and cASBP, cADBP and PWV in HD patients. Replacement of O. formigenes with pre- and probiotics might decrease serum oxalic acid levels and improve cardiovascular outcomes in HD patients. PMID:26195968

The Relationship between Serum Oxalic Acid, Central Hemodynamic Parameters and Colonization by Oxalobacter formigenes in Hemodialysis Patients.

PubMed

Gulhan, Baris; Turkmen, Kultigin; Aydin, Merve; Gunay, Murat; Cıkman, Aytekin; Kara, Murat

2015-06-01

Elevated pulse wave velocity (PWV) and central aortic blood pressures are independent predictors of increased cardiovascular morbidity and mortality in hemodialysis (HD) patients. Oxalic acid is a uremic retention molecule that is extensively studied in the pathogenesis of calcium oxalate stones. Oxalobacter formigenes, a member of the colon microbiota, has important roles in oxalate homeostasis. Data regarding the colonization by and the exact role of O. formigenes in the pathogenesis of oxalic acid metabolism in HD patients are scant. Hence, we aimed to determine the relationship between fecal O. formigenes colonization, serum oxalic acid and hemodynamic parameters in HD patients with regard to the colo-reno-cardiac axis. Fifty HD patients were enrolled in this study. PWV and central aortic systolic (cASBP) and diastolic blood pressures (cADBP) were measured with a Mobil-O-Graph (I.E.M. GmbH, Stolberg, Germany). Serum oxalic acid levels were assessed by ELISA, and fecal O. formigenes DNA levels were isolated and measured by real-time PCR. Isolation of fecal O. formigenes was found in only 2 HD patients. One of them had 113,609 copies/ml, the other one had 1,056 copies/ml. Serum oxalic acid levels were found to be positively correlated with PWV (r = 0.29, p = 0.03), cASBP (r = 0.33, p = 0.001) and cADBP (r = 0.42, p = 0.002) and negatively correlated with LDL (r = -0.30, p = 0.03). In multivariate linear regression analysis, PWV was independently predicted by oxalic acid, glucose and triglyceride. This is the first study that demonstrates the absence of O. formigenes as well as a relation between serum oxalic acid and cASBP, cADBP and PWV in HD patients. Replacement of O. formigenes with pre- and probiotics might decrease serum oxalic acid levels and improve cardiovascular outcomes in HD patients.

The effect of ascorbic acid ingestion on the biochemical and physicochemical risk factors associated with calcium oxalate kidney stone formation.

PubMed

Auer, B L; Auer, D; Rodgers, A L

1998-03-01

The present study was undertaken to determine the effect of ingestion of large doses of vitamin C on urinary oxalate excretion and on a number of other biochemical and physicochemical risk factors associated with calcium oxalate urolithiasis. A further objective was to determine urinary ascorbate excretion and to relate it qualitatively to ingested levels of the vitamin and oxalate excretion. Ten healthy males participated in a protocol in which 4 g ascorbic acid was ingested for 5 days. Urines (24 h) were collected prior to, during and after the protocol. The urine collection procedure was designed to allow for the analysis of oxalate in the presence and absence of an EDTA preservative and for the analysis of ascorbic acid by manual titration using 2,6 dichlorophenolindophenol. Physicochemical risk factors such as the calcium oxalate relative supersaturation and Tiselius risk index were calculated from urine composition. The results showed that erroneously high analytical oxalate levels occur in the asence of preservative. In the preserved samples there was no significant increase in oxalate excretion at any stage of the protocol. Ascorbate excretion increased when vitamin C ingestion commenced but levelled out after 24 hours suggesting that saturation of the metabolic pool is reached within 24 hours after which ingested ascorbic acid is excreted unmetabolized in the urine. While transient statistically significant changes occurred in some of the biochemical risk factors, they were not regarded as being clinically significant. There were no changes in either the calcium oxalate relative supersaturation or Tiselius risk index. It is concluded that ingestion of large doses of ascorbic acid does not affect the principal risk factors associated with calcium oxalate kidney stone formation.

Oxidation of aquatic pollutants by ferrous-oxalate complexes under dark aerobic conditions.

PubMed

Lee, Jaesang; Kim, Jungwon; Choi, Wonyong

2014-06-15

This study evaluates the ability of Fe(II)-oxalate complexes for the generation of OH through oxygen reduction and the oxidative degradation of aquatic pollutants under dark aerobic conditions (i.e., with oxygen but without light). The degradation of 4-chlorophenol (4-CP) was rapid in the mixture of Fe(2+) and oxalate prepared using ultrapure water, but was absent without either Fe(2+) or oxalate. The formation of Fe(II)-oxalate complexes enables two-electron reduction of oxygen to generate H2O2 and subsequent production of OH. The significant inhibition of 4-CP degradation in the presence of H2O2 and OH scavenger confirms such mechanisms. The degradation experiments with varying [Fe(2+)], [oxalate], and initial pH demonstrated that the degradation rate depends on [Fe(II)(Ox)2(2-)], but the degree of degradation is primarily determined by [Fe(II)(Ox)2(2-)]+[Fe(II)(Ox)(0)]. Efficient degradation of diverse aquatic pollutants, especially phenolic pollutants, was observed in the Fe(II)-oxalate complexes system, wherein the oxidation efficacy was primarily correlated with the reaction rate constant between pollutant and OH. The effect of various organic ligands (oxalate, citrate, EDTA, malonate, and acetate) on the degradation kinetics of 4-CP was investigated. The highest efficiency of oxalate for the oxidative degradation is attributed to its high capability to enhance the reducing power and low reactivity with OH. Copyright © 2014 Elsevier B.V. All rights reserved.

Function and X-Ray crystal structure of Escherichia coli YfdE

PubMed Central

Mullins, Elwood A.; Sullivan, Kelly L.; Kappock, T. Joseph

2013-01-01

Many food plants accumulate oxalate, which humans absorb but do not metabolize, leading to the formation of urinary stones. The commensal bacterium Oxalobacter formigenes consumes oxalate by converting it to oxalyl-CoA, which is decarboxylated by oxalyl-CoA decarboxylase (OXC). OXC and the class III CoA-transferase formyl-CoA:oxalate CoA-transferase (FCOCT) are widespread among bacteria, including many that have no apparent ability to degrade or to resist external oxalate. The EvgA acid response regulator activates transcription of the Escherichia coli yfdXWUVE operon encoding YfdW (FCOCT), YfdU (OXC), and YfdE, a class III CoA-transferase that is 30% identical to YfdW. YfdW and YfdU are necessary and sufficient for oxalate-induced protection against a subsequent acid challenge; neither of the other genes has a known function. We report the purification, in vitro characterization, 2.1-Å crystal structure, and functional assignment of YfdE. YfdE and UctC, an orthologue from the obligate aerobe Acetobacter aceti, perform the reversible conversion of acetyl-CoA and oxalate to oxalyl-CoA and acetate. The annotation of YfdE as acetyl-CoA:oxalate CoA-transferase (ACOCT) expands the scope of metabolic pathways linked to oxalate catabolism and the oxalate-induced acid tolerance response. FCOCT and ACOCT active sites contain distinctive, conserved active site loops (the glycine-rich loop and the GNxH loop, respectively) that appear to encode substrate specificity. PMID:23935849

Coulometric Study of Rates of Oxalic Acid Adsorption at a Polycrystalline Platinum Electrode

DTIC Science & Technology

2012-09-01

Coulometric Study of Rates of Oxalic Acid Adsorption at a Polycrystalline Platinum Electrode by Sol Gilman ARL-TR-6165 September 2012...6165 September 2012 Coulometric Study of Rates of Oxalic Acid Adsorption at a Polycrystalline Platinum Electrode Sol Gilman Sensors and...3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Coulometric Study of Rates of Oxalic Acid Adsorption at a Polycrystalline Platinum Electrode

C-Phycocyanin Confers Protection against Oxalate-Mediated Oxidative Stress and Mitochondrial Dysfunctions in MDCK Cells

PubMed Central

Farooq, Shukkur M.; Boppana, Nithin B.; Asokan, Devarajan; Sekaran, Shamala D.; Shankar, Esaki M.; Li, Chunying; Gopal, Kaliappan; Bakar, Sazaly A.; Karthik, Harve S.; Ebrahim, Abdul S.

2014-01-01

Oxalate toxicity is mediated through generation of reactive oxygen species (ROS) via a process that is partly dependent on mitochondrial dysfunction. Here, we investigated whether C-phycocyanin (CP) could protect against oxidative stress-mediated intracellular damage triggered by oxalate in MDCK cells. DCFDA, a fluorescence-based probe and hexanoyl-lysine adduct (HEL), an oxidative stress marker were used to investigate the effect of CP on oxalate-induced ROS production and membrane lipid peroxidation (LPO). The role of CP against oxalate-induced oxidative stress was studied by the evaluation of mitochondrial membrane potential by JC1 fluorescein staining, quantification of ATP synthesis and stress-induced MAP kinases (JNK/SAPK and ERK1/2). Our results revealed that oxalate-induced cells show markedly increased ROS levels and HEL protein expression that were significantly decreased following pre-treatment with CP. Further, JC1 staining showed that CP pre-treatment conferred significant protection from mitochondrial membrane permeability and increased ATP production in CP-treated cells than oxalate-alone-treated cells. In addition, CP treated cells significantly decreased the expression of phosphorylated JNK/SAPK and ERK1/2 as compared to oxalate-alone-treated cells. We concluded that CP could be used as a potential free radical-scavenging therapeutic strategy against oxidative stress-associated diseases including urolithiasis. PMID:24691130

Naked-eye determination of oxalate anion in aqueous solution with copper ion and pyrocatechol violet.

PubMed

Su, Jing; Sun, Yuan-Qiang; Huo, Fang-Jun; Yang, Yu-Tao; Yin, Cai-Xia

2010-11-01

A novel strategy for the determination of oxalate anions was successfully established using a copper ion and pyrocatechol violet (PV) ensemble. The sensor ensemble can discriminate oxalate over other common anions including F(-), Cl(-), I(-), Br(-), HPO(4)(2-), PO(4)(3-), AcO(-), CO(3)(2-), SO(4)(2-), ClO(4)(-), P(2)O(7)(4-), S(2-) (deposited by Ag(+)), CN(-) (shielded by Fe(3+)) and can detect oxalate at low microgram levels in quasi-physiological aqueous solutions. The detection of the oxalate anion gives rise to a rapid observable visual color change from blue to yellow.

Flow-driven pattern formation in the calcium-oxalate system.

PubMed

Bohner, Bíborka; Endrődi, Balázs; Horváth, Dezső; Tóth, Ágota

2016-04-28

The precipitation reaction of calcium oxalate is studied experimentally in the presence of spatial gradients by controlled flow of calcium into oxalate solution. The density difference between the reactants leads to strong convection in the form of a gravity current that drives the spatiotemporal pattern formation. The phase diagram of the system is constructed, the evolving precipitate patterns are analyzed and quantitatively characterized by their diameters and the average height of the gravity flow. The compact structures of calcium oxalate monohydrate produced at low flow rates are replaced by the thermodynamically unstable calcium oxalate dihydrate favored in the presence of a strong gravity current.

The genetic composition of Oxalobacter formigenes and its relationship to colonization and calcium oxalate stone disease

PubMed Central

Knight, John; Deora, Rajendar; Assimos, Dean G.; Holmes, Ross P.

2013-01-01

Oxalobacter formigenes is a unique intestinal organism that relies on oxalate degradation to meet most of its energy and carbon needs. A lack of colonization is a risk factor for calcium oxalate stone disease. Protection against calcium oxalate stone disease appears to be due to the oxalate degradation that occurs in the gut on low calcium diets with a possible further contribution from intestinal oxalate secretion. Much remains to be learned about how the organism establishes and maintains gut colonization and the precise mechanisms by which it modifies stone risk. The sequencing and annotation of the genomes of a Group 1 and a Group 2 strain of O. formigenes should provide the informatic tools required for the identification of the genes and pathways associated with colonization and survival. In this review we have identified genes that may be involved and where appropriate suggested how they may be important in calcium oxalate stone disease. Elaborating the functional roles of these genes should accelerate our understanding of the organism and clarify its role in preventing stone formation. PMID:23632911

Acute oxalate nephropathy after ingestion of star fruit.

PubMed

Chen, C L; Fang, H C; Chou, K J; Wang, J S; Chung, H M

2001-02-01

Acute oxalate nephropathy associated with ingestion of star fruit (carambola) has not been reported before. We report the first two cases. These patients developed nausea, vomiting, abdominal pain, and backache within hours of ingesting large quantities of sour carambola juice; then acute renal failure followed. Both patients needed hemodialysis for oliguric acute renal failure, and pathologic examinations showed typical changes of acute oxalate nephropathy. The renal function recovered 4 weeks later without specific treatment. Sour carambola juice is a popular beverage in Taiwan. The popularity of star fruit juice is not compatible with the rare discovery of star fruit-associated acute oxalate nephropathy. Commercial carambola juice usually is prepared by pickling and dilution processes that reduce oxalate content markedly, whereas pure fresh juice or mild diluted postpickled juice for traditional remedies, as used in our cases, contain high quantities of oxalate. An empty stomach and dehydrated state may pose an additional risk for development of renal injury. To avoid acute oxalate nephropathy, pure sour carambola juice or mild diluted postpickled juice should not be consumed in large amounts, especially on an empty stomach or in a dehydrated state.

Vitamin D Supplementation in Submariners

DTIC Science & Technology

2008-12-02

prevalence of over 10% in men.71 Most stones are composed of calcium oxalate or calcium phosphate.72 It is the composition of these stones that...urine that combine with calcium to form calcium oxalate stones.77 One of the major factors that reduce hyperoxaluria is calcium in the diet. The... calcium in the intestinal lumen forms insoluble calcium salts with the oxalates and is not absorbed. A diet low in calcium will allow more oxalates to be

Perchlorate and Halogen-Free High Energy Dense Oxidizers (HEDO)

DTIC Science & Technology

2011-06-01

nitric acid indicate that the covalent oxalic acid dinitrate ester should be more stable than the ionic dinitronium oxalate . The following three...synthetic strategies were developed to generate compound 11 (Scheme 17). Strategy I is the nitration of anhydrous oxalic acid with nitric acid (100...temperatures (25 to –30 °C) and in all dry solvents used. Scheme 17: Synthetic strategies for the production of oxalic acid dinitrate ester (11

Preparation and Stoichiometry Effects on Microstructure and Properties of High Purity BaTiO3.

DTIC Science & Technology

1986-03-27

oxalate , citrate) salt solutions, from mixed alkoxide precursors or from hydrothermal solutions. Typical starting materials and reaction sequences...decomposition and calcination reactions to form the BaTiO compound. Both the oxalate and 3 hydrothermal processes show commnercial promise and are briefly...thermal decomposition of oxalates and by hydrothermal synthesis. As-received lots of mixed oxide and oxalate -derived powders had Ba:TI ratios of 0.997 and

Chemical composition and binary mixture of human urinary stones using FT-Raman spectroscopy method.

PubMed

Selvaraju, R; Raja, A; Thiruppathi, G

2013-10-01

In the present study the human urinary stones were observed in their different chemical compositions of calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate, struvite (magnesium ammonium phosphate), uric acid, cystine, oxammite (ammonium oxalate monohydrate), natroxalate (sodium oxalate), glushinkite (magnesium oxalate dihydrate) and moolooite (copper oxalate) were analyzed using Fourier Transform-Raman (FT-Raman) spectroscopy. For the quantitative analysis, various human urinary stone samples are used for ratios calculation of binary mixtures compositions such as COM/COD, HAP/COD, HAP/COD, Uric acid/COM, uric acid/COD and uric acid/HAP. The calibration curve is used for further analysis of binary mixture of human urinary stones. For the binary mixture calculation the various intensities bands at 1462 cm(-1) (I(COM)), 1473 cm(-1) (I(COD)), 961 cm(-1) (I(HAP)) and 1282 cm(-1) (I(UA)) were used. Copyright © 2013 Elsevier B.V. All rights reserved.

Facile fabrication of cobalt oxalate nanostructures with superior specific capacitance and super-long cycling stability

NASA Astrophysics Data System (ADS)

Cheng, Guanhua; Si, Conghui; Zhang, Jie; Wang, Ying; Yang, Wanfeng; Dong, Chaoqun; Zhang, Zhonghua

2016-04-01

Transition metal oxalate materials have shown huge competitive advantages for applications in supercapacitors. Herein, nanostructured cobalt oxalate supported on cobalt foils has been facilely fabricated by anodization, and could directly serve as additive/binder-free electrodes for supercapacitors. The as-prepared cobalt oxalate electrodes present superior specific capacitance of 1269 F g-1 at the current density of 6 A g-1 in the galvanostatic charge/discharge test. Moreover, the retained capacitance is as high as 87.2% as the current density increases from 6 A g-1 to 30 A g-1. More importantly, the specific capacitance of cobalt oxalate retains 91.9% even after super-long cycling of 100,000 cycles. In addition, an asymmetric supercapacitor assembled with cobalt oxalate (positive electrode) and activated carbon (negative electrode) demonstrates excellent capacitive performance with high energy density and power density.

ADVANCED OXIDATION: OXALATE DECOMPOSITION TESTING WITH OZONE

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

Ketusky, E.; Subramanian, K.

At the Savannah River Site (SRS), oxalic acid is currently considered the preferred agent for chemically cleaning the large underground Liquid Radioactive Waste Tanks. It is applied only in the final stages of emptying a tank when generally less than 5,000 kg of waste solids remain, and slurrying based removal methods are no-longer effective. The use of oxalic acid is preferred because of its combined dissolution and chelating properties, as well as the fact that corrosion to the carbon steel tank walls can be controlled. Although oxalic acid is the preferred agent, there are significant potential downstream impacts. Impacts include:more » (1) Degraded evaporator operation; (2) Resultant oxalate precipitates taking away critically needed operating volume; and (3) Eventual creation of significant volumes of additional feed to salt processing. As an alternative to dealing with the downstream impacts, oxalate decomposition using variations of ozone based Advanced Oxidation Process (AOP) were investigated. In general AOPs use ozone or peroxide and a catalyst to create hydroxyl radicals. Hydroxyl radicals have among the highest oxidation potentials, and are commonly used to decompose organics. Although oxalate is considered among the most difficult organic to decompose, the ability of hydroxyl radicals to decompose oxalate is considered to be well demonstrated. In addition, as AOPs are considered to be 'green' their use enables any net chemical additions to the waste to be minimized. In order to test the ability to decompose the oxalate and determine the decomposition rates, a test rig was designed, where 10 vol% ozone would be educted into a spent oxalic acid decomposition loop, with the loop maintained at 70 C and recirculated at 40L/min. Each of the spent oxalic acid streams would be created from three oxalic acid strikes of an F-area simulant (i.e., Purex = high Fe/Al concentration) and H-area simulant (i.e., H area modified Purex = high Al/Fe concentration) after nearing dissolution equilibrium, and then decomposed to {le} 100 Parts per Million (ppm) oxalate. Since AOP technology largely originated on using ultraviolet (UV) light as a primary catalyst, decomposition of the spent oxalic acid, well exposed to a medium pressure mercury vapor light was considered the benchmark. However, with multi-valent metals already contained in the feed, and maintenance of the UV light a concern; testing was conducted to evaluate the impact from removing the UV light. Using current AOP terminology, the test without the UV light would likely be considered an ozone based, dark, ferrioxalate type, decomposition process. Specifically, as part of the testing, the impacts from the following were investigated: (1) Importance of the UV light on the decomposition rates when decomposing 1 wt% spent oxalic acid; (2) Impact of increasing the oxalic acid strength from 1 to 2.5 wt% on the decomposition rates; and (3) For F-area testing, the advantage of increasing the spent oxalic acid flowrate from 40 L/min (liters/minute) to 50 L/min during decomposition of the 2.5 wt% spent oxalic acid. The results showed that removal of the UV light (from 1 wt% testing) slowed the decomposition rates in both the F & H testing. Specifically, for F-Area Strike 1, the time increased from about 6 hours to 8 hours. In H-Area, the impact was not as significant, with the time required for Strike 1 to be decomposed to less than 100 ppm increasing slightly, from 5.4 to 6.4 hours. For the spent 2.5 wt% oxalic acid decomposition tests (all) without the UV light, the F-area decompositions required approx. 10 to 13 hours, while the corresponding required H-Area decompositions times ranged from 10 to 21 hours. For the 2.5 wt% F-Area sludge, the increased availability of iron likely caused the increased decomposition rates compared to the 1 wt% oxalic acid based tests. In addition, for the F-testing, increasing the recirculation flow rates from 40 liter/minute to 50 liter/minute resulted in an increased decomposition rate, suggesting a better use of ozone.« less

Antilithiatic Activity of phlorotannin rich extract of Sarghassum Wightii on Calcium Oxalate Urolithiais – In Vitro and In Vivo Evaluation

PubMed Central

Sujatha, D.; Singh, Kiranpal; Vohra, Mursalin; Kumar, K. Vijay; Sunitha, S.

2015-01-01

ABSTRACT Purpose: Urolithiasis is a common urological disorder responsible for serious human affliction and cost to the society with a high recurrence rate. The aim of the present study was to systematically evaluate the phlorotannin rich extract of Sargassum wightii using suitable in vitro and in vivo models to provide scientific evidence for its antilithiatic activity. Materials and Methods: To explore the effect of Sargassum wightii on calcium oxalate crystallization, in vitro assays like crystal nucleation, aggregation and crystal growth were performed. Calcium oxalate urolithiasis was induced in male Sprague dawley rats using a combination of gentamicin and calculi producing diet (5% ammonium oxalate and rat pellet feed). The biochemical parameters like calcium, oxalate, magnesium, phosphate, sodium and potassium were evaluated in urine, serum and kidney homogenates. Histopathological studies were also done to confirm the biochemical findings. Results: The yield of Sargassum wightii extract was found to be 74.5 gm/kg and confirmed by quantitative analysis. In vitro experiments with Sargassum wightii showed concentration dependent inhibition of calcium oxalate nucleation, aggregation and growth supported by SEM analysis. In the in vivo model, Sargassum wightii reduced both calcium and oxalate supersaturation in urine, serum and deposition in the kidney. The biochemical results were supported by histopathological studies. Conclusion: The findings of the present study suggest that Sargassum wightii has the ability to prevent nucleation, aggregation and growth of calcium oxalate crystals. Sargassum wightii has better preventive effect on calcium oxalate stone formation indicating its strong potential to develop as a therapeutic option to prevent recurrence of urolithiasis. PMID:26200544

Relative hyperoxaluria, crystalluria and haematuria after megadose ingestion of vitamin C.

PubMed

Auer, B L; Auer, D; Rodgers, A L

1998-09-01

Long-term or high-dosage consumption of vitamin C may play a role in calcium oxalate kidney stone formation. The present study was undertaken to determine the biochemical and physicochemical risk factors in a male subject who developed haematuria and calcium oxalate crystalluria after ingestion of large doses of ascorbic acid for 8 consecutive days. Twenty-four-hour urine samples were collected before and during the ascorbic acid ingestion period as well as after the detection of haematuria. A special procedure was implemented for urine collections to allow for oxalate, ascorbate and other urinalysis. Oxalate was determined in the presence of EDTA to prevent in vitro conversion to ascorbic acid, whereas ascorbate itself was determined by manual titration in a redox method using the dye dichlorophenolindophenol. Urinalysis data were used to compute calcium oxalate relative supersaturations and Tiselius risk indices, whereas scanning electron microscopy was used to examine urinary deposits. Oxalate excretion increased by about 350% during ascorbate ingestion before haematuria. Ascorbate concentrations also increased dramatically but appeared to reach a plateau maximum. Increasing calcium excretion was accompanied by decreasing potassium and phosphate values. The calcium oxalate relative supersaturation and Tiselius risk index increased during vitamin C ingestion and large aggregates of calcium oxalate dihydrate crystals were observed by scanning electron microscopy immediately after the detection of haematuria. High percentage metabolic conversion of ascorbate to oxalate in this subject caused relative hyperoxaluria and crystalluria, the latter manifesting itself as haematuria. Clinicians need to be alerted to the potential dangers of large dose ingestion of vitamin C in some individuals.

A Human Strain of Oxalobacter (HC-1) Promotes Enteric Oxalate Secretion in the Small Intestine of Mice and Reduces Urinary Oxalate Excretion

PubMed Central

Hatch, Marguerite; Freel, Robert W.

2013-01-01

Enteric oxalate secretion that correlated with reductions in urinary oxalate excretion was previously reported in a mouse model of Primary Hyperoxaluria, and in wild type (WT) mice colonized with a wild rat strain (OXWR) of Oxalobacter (Am J Physiol 300: G461-G469, 2011). Since a human strain of the bacterium is more likely to be clinically used as a probiotic therapeutic, we tested the effects of HC-1 in WT. Following artificial colonization of WT mice with HC-1, the bacteria were confirmed to be present in the large intestine and, unexpectedly, detected in the small intestine for varying periods of time. The main objective of the present study was to determine whether the presence of HC-1 promoted intestinal secretion in the more proximal segments of the gastrointestinal tract. In addition, we determined whether HC-1 colonization led to reductions in urinary oxalate excretion in these mice. The results show that the human Oxalobacter strain promotes a robust net secretion of oxalate in the distal ileum as well as in the caecum and distal colon and these changes in transport correlate with the beneficial effect of reducing renal excretion of oxalate. We conclude that OXWR effects on intestinal oxalate transport and oxalate homeostasis are not unique to the wild rat strain and that, mechanistically, HC-1 has significant potential for use as a probiotic treatment for hyperoxaluria especially if it is also targeted to the upper and lower gastrointestinal tract. PMID:23959075

Effect of Kimchi Fermentation on Oxalate Levels in Silver Beet (Beta vulgaris var. cicla)

PubMed Central

Wadamori, Yukiko; Vanhanen, Leo; Savage, Geoffrey P.

2014-01-01

Total, soluble and insoluble oxalates were extracted and analyzed by high performance liquid chromatography (HPLC) following the preparation of kimchi using silver beet (Beta vulgaris var. cicla) stems and leaves. As silver beet contains high oxalate concentrations and consumption of high levels can cause the development of kidney stones in some people, the reduction of oxalate during preparation and fermentation of kimchi was investigated. The silver beet stems and leaves were soaked in a 10% brine solution for 11 h and then washed in cold tap water. The total, soluble and insoluble oxalate contents of the silver beet leaves were reduced by soaking in brine, from 4275.81 ± 165.48 mg/100 g to 3709.49 ± 216.51 mg/100 g fresh weight (FW). Fermenting the kimchi for 5 days at 19.3 ± 0.8 °C in 5 L ceramic jars with a water airtight seal resulted in a mean 38.50% reduction in total oxalate content and a mean 22.86% reduction in soluble oxalates. The total calcium content was essentially the same before and after the fermentation of the kimchi (mean 296.1 mg/100 g FW). The study showed that fermentation of kimchi significantly (p < 0.05) reduced the total oxalate concentration in the initial mix from 609.32 ± 15.69 to 374.71 ± 7.94 mg/100 g FW in the final mix which led to a 72.3% reduction in the amount of calcium bound to insoluble oxalate. PMID:28234318

In-cloud oxalate formation in the global troposphere: a 3-D modeling study

NASA Astrophysics Data System (ADS)

Myriokefalitakis, S.; Tsigaridis, K.; Mihalopoulos, N.; Sciare, J.; Nenes, A.; Segers, A.; Kanakidou, M.

2011-01-01

Organic acids attract increasing attention as contributors to atmospheric acidity, secondary organic aerosol mass and aerosol hygroscopicity. Oxalic acid is globally the most abundant dicarboxylic acid, formed via chemical oxidation of gas-phase precursors in the aqueous phase of aerosols and droplets. Its lifecycle and atmospheric global distribution remain highly uncertain and are the focus of this study. The first global spatial and temporal distribution of oxalate, simulated using a state-of-the-art aqueous phase chemical scheme embedded within the global 3-dimensional chemistry/transport model TM4-ECPL, is here presented. The model accounts for comprehensive gas-phase chemistry and its coupling with major aerosol constituents (including secondary organic aerosol). Model results are consistent with ambient observations of oxalate at rural and remote locations (slope = 0.83 ± 0.06, r2 = 0.67, N = 106) and suggest that aqueous phase chemistry contributes significantly to the global atmospheric burden of secondary organic aerosol. In TM4-ECPL most oxalate is formed in-clouds and less than 10% is produced in aerosol water. About 61% of the oxalate is removed via wet deposition, 35% by in-cloud reaction with hydroxyl radical and 4% by dry deposition. The global oxalate net chemical production is calculated to be about 17-27 Tg yr-1 with almost 91% originating from biogenic hydrocarbons, mainly isoprene. This condensed phase net source of oxalate in conjunction with a global mean turnover time against deposition of about 5 days, maintain oxalate's global tropospheric burden of 0.24-0.39 Tg that is about 13-19% of calculated total organic aerosol burden.

Evidence of a natural marine source of oxalic acid and a possible link to glyoxal

NASA Astrophysics Data System (ADS)

Rinaldi, Matteo; Decesari, Stefano; Carbone, Claudio; Finessi, Emanuela; Fuzzi, Sandro; Ceburnis, Darius; O'Dowd, Colin D.; Sciare, Jean; Burrows, John P.; Vrekoussis, Mihalis; Ervens, Barbara; Tsigaridis, Kostas; Facchini, Maria Cristina

2011-08-01

This paper presents results supporting the existence of a natural source of oxalic acid over the oceans. Oxalate was detected in "clean-sector" marine aerosol samples at Mace Head (Ireland) (53°20'N, 9°54'W) during 2006, and at Amsterdam Island (37°48'S, 77°34'E) from 2003 to 2007, in concentrations ranging from 2.7 to 39 ng m-3 and from 0.31 to 17 ng m-3, respectively. The oxalate concentration showed a clear seasonal trend at both sites, with maxima in spring-summer and minima in fall-winter, being consistent with other marine biogenic aerosol components (e.g., methanesulfonic acid, non-sea-salt sulfate, and aliphatic amines). The observed oxalate was distributed along the whole aerosol size spectrum, with both a submicrometer and a supermicrometer mode, unlike the dominant submicrometer mode encountered in many polluted environments. Given its mass size distribution, the results suggest that over remote oceanic regions oxalate is produced through a combination of different formation processes. It is proposed that the cloud-mediated oxidation of gaseous glyoxal, recently detected over remote oceanic regions, may be an important source of submicrometer oxalate in the marine boundary layer. Supporting this hypothesis, satellite-retrieved glyoxal column concentrations over the two sampling sites exhibited the same seasonal concentration trend of oxalate. Furthermore, chemical box model simulations showed that the observed submicrometer oxalate concentrations were consistent with the in-cloud oxidation of typical marine air glyoxal mixing ratios, as retrieved by satellite measurements, at both sites.

The oxalate-carbonate pathway: at the interface between biology and geology

NASA Astrophysics Data System (ADS)

Junier, P.; Cailleau, G.; Martin, G.; Guggiari, M.; Bravo, D.; Clerc, M.; Aragno, M.; Job, D.; Verrecchia, E.

2012-04-01

The formation of calcite in otherwise carbonate-free acidic soils through the biological degradation of oxalate is a mechanism termed oxalate-carbonate pathway. This pathway lies at the interface between biological and geological systems and constitutes an important, although underestimated, soil mineral carbon sink. In this case, atmospheric CO2 is fixed by the photosynthetic activity of oxalogenic plants, which is partly destined to the production of oxalate used for the chelation of metals, and particularly, calcium. Fungi are also able to produce oxalate to cope with elevated concentrations of metals. In spite of its abundance as a substrate, oxalate is a very stable organic anion that can be metabolized only by a group of bacteria that use it as carbon and energy sources. These bacteria close the biological cycle by degrading calcium oxalate, releasing Ca2+ and inducing a change in local soil pH. If parameters are favourable, the geological part of the pathway begins, because this change in pH will indirectly lead to the precipitation of secondary calcium carbonate (calcite) in unexpected geological conditions. Due to the initial acidic soil conditions, and the absence of geological carbonate in the basement, it is unexpected to find C in the form of calcite. The activity of the oxalate-carbonate pathway has now been demonstrated in several places around the world, suggesting that its importance can be even greater than expected. In addition, new roles for each of the biological players of the pathway have been revealed recently forcing us to reconsider a global biogeochemical model for oxalate cycling.

OXALATE DEPOSITION ON ASBESTOS BODIES

EPA Science Inventory

The clinical and histopathologic findings in three patients with a deposition of calcium oxalate crystals on ferruginous bodies after occupational exposure to asbestos are provided. In addition, we test the hypothesis that this oxalate can be generated through a nonenzymatic o...

Enhanced Chemical Cleaning: A New Process for Chemically Cleaning Savannah River Waste Tanks

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

Ketusky, Edward; Spires, Renee; Davis, Neil

2009-02-11

At the Savannah River Site (SRS) there are 49 High Level Waste (HLW) tanks that eventually must be emptied, cleaned, and closed. The current method of chemically cleaning SRS HLW tanks, commonly referred to as Bulk Oxalic Acid Cleaning (BOAC), requires about a half million liters (130,000 gallons) of 8 weight percent (wt%) oxalic acid to clean a single tank. During the cleaning, the oxalic acid acts as the solvent to digest sludge solids and insoluble salt solids, such that they can be suspended and pumped out of the tank. Because of the volume and concentration of acid used, amore » significant quantity of oxalate is added to the HLW process. This added oxalate significantly impacts downstream processing. In addition to the oxalate, the volume of liquid added competes for the limited available tank space. A search, therefore, was initiated for a new cleaning process. Using TRIZ (Teoriya Resheniya Izobretatelskikh Zadatch or roughly translated as the Theory of Inventive Problem Solving), Chemical Oxidation Reduction Decontamination with Ultraviolet Light (CORD-UV{reg_sign}), a mature technology used in the commercial nuclear power industry was identified as an alternate technology. Similar to BOAC, CORD-UV{reg_sign} also uses oxalic acid as the solvent to dissolve the metal (hydr)oxide solids. CORD-UV{reg_sign} is different, however, since it uses photo-oxidation (via peroxide/UV or ozone/UV to form hydroxyl radicals) to decompose the spent oxalate into carbon dioxide and water. Since the oxalate is decomposed and off-gassed, CORD-UV{reg_sign} would not have the negative downstream oxalate process impacts of BOAC. With the oxalate destruction occurring physically outside the HLW tank, re-precipitation and transfer of the solids, as well as regeneration of the cleaning solution can be performed without adding additional solids, or a significant volume of liquid to the process. With a draft of the pre-conceptual Enhanced Chemical Cleaning (ECC) flowsheet, taking full advantage of the many CORD-UV{reg_sign} benefits, performance demonstration testing was initiated using available SRS sludge simulant. The demonstration testing confirmed that ECC is a viable technology, as it can dissolve greater than 90% of the sludge simulant and destroy greater than 90% of the oxalates. Additional simulant and real waste testing are planned.« less

A specific role for serotonin in overcoming effort cost.

PubMed

Meyniel, Florent; Goodwin, Guy M; Deakin, Jf William; Klinge, Corinna; MacFadyen, Christine; Milligan, Holly; Mullings, Emma; Pessiglione, Mathias; Gaillard, Raphaël

2016-11-08

Serotonin is implicated in many aspects of behavioral regulation. Theoretical attempts to unify the multiple roles assigned to serotonin proposed that it regulates the impact of costs, such as delay or punishment, on action selection. Here, we show that serotonin also regulates other types of action costs such as effort. We compared behavioral performance in 58 healthy humans treated during 8 weeks with either placebo or the selective serotonin reuptake inhibitor escitalopram. The task involved trading handgrip force production against monetary benefits. Participants in the escitalopram group produced more effort and thereby achieved a higher payoff. Crucially, our computational analysis showed that this effect was underpinned by a specific reduction of effort cost, and not by any change in the weight of monetary incentives. This specific computational effect sheds new light on the physiological role of serotonin in behavioral regulation and on the clinical effect of drugs for depression. ISRCTN75872983.

Cotard's Syndrome after breast surgery successfully treated with aripiprazole augmentation of escitalopram: a case report.

PubMed

De Berardis, Domenico; Brucchi, Maurizio; Serroni, Nicola; Rapini, Gabriella; Campanella, Daniela; Vellante, Federica; Valchera, Alessandro; Fornaro, Michele; Iasevoli, Felice; Mazza, Monica; Lucidi, Giuliana; Martinotti, Giovanni; di Giannantonio, Massimo

2015-01-01

In 1880 the French neurologist Jules Cotard described a condition characterized by delusion of negation (nihilistic delusion) in a melancholia context. Recently, there has been a resurgence of interest in Cotard's syndrome (CS), but the nosographical figure of CS remains unclear. It isn't determined if it pertains to the delusional themes area or if it is related to the sense of immanent ruin in some depressive episodes. For these reasons CS has recently been supposed to be an intermediate form. Furthermore, since even less is known about secondary CS in subjects who had never suffered of psychiatric disorders, in the present case we report the development of a secondary CS in a female patient who underwent a lumpectomy for the removal of a benign fibroadenoma. The patient responded well to aripiprazole augmentation of escitalopram and totally remitted.

Atmospheric production of oxalic acid/oxalate and nitric acid/nitrate in the Tampa Bay airshed: Parallel pathways

NASA Astrophysics Data System (ADS)

Martinelango, P. Kalyani; Dasgupta, Purnendu K.; Al-Horr, Rida S.

Oxalic acid is the dominant dicarboxylic acid (DCA), and it constitutes up to 50% of total atmospheric DCAs, especially in non-urban and marine atmospheres. A significant amount of particulate H 2Ox/oxalate (Ox) occurred in the coarse particle fraction of a dichotomous sampler, the ratio of oxalate concentrations in the PM 10 to PM 2.5 fractions ranged from 1 to 2, with mean±sd being 1.4±0.2. These results suggest that oxalate does not solely originate in the gas phase and condense into particles. Gaseous H 2Ox concentrations are much lower than particulate Ox concentrations and are well correlated with HNO 3, HCHO, and O 3, supporting a photochemical origin. Of special relevance to the Bay Region Atmospheric Chemistry Experiment (BRACE) is the extent of nitrogen deposition in the Tampa Bay estuary. Hydroxyl radical is primarily responsible for the conversion of NO 2 to HNO 3, the latter being much more easily deposited. Hydroxyl radical is also responsible for the aqueous phase formation of oxalic acid from alkenes. Hence, we propose that an estimate of rad OH can be obtained from H 2Ox/Ox production rate and we accordingly show that the product of total oxalate concentration and NO 2 concentration approximately predicts the total nitrate concentration during the same period.

Nanoscale observations of the effect of citrate on calcium oxalate precipitation on calcite surfaces.

NASA Astrophysics Data System (ADS)

Burgos-Cara, Alejandro; Ruiz-Agudo, Encarnacion; Putnis, Christine V.

2016-04-01

Calcium oxalate (CaC2O4ṡxH2O) minerals are naturally occurring minerals found in fossils, plants, kidney stones and is a by-product in some processes such as paper, food and beverage production [1,2]. In particular, calcium oxalate monohydrate phase (COM) also known as whewellite (CaC2O4ṡH2O), is the most frequently reported mineral phase found in urinary and kidney stones together with phosphates. Organic additives are well known to play a key role in the formation of minerals in both biotic and abiotic systems, either facilitating their precipitation or hindering it. In this regard, recent studies have provided direct evidence demonstrating that citrate species could enhance dissolution of COM and inhibit their precipitation. [3,4] The present work aims at evauate the influence of pH, citrate and oxalic acid concentrations in calcium oxalate precipitation on calcite surfaces (Island Spar, Chihuahua, Mexico) through in-situ nanoscale observation using in situ atomic force microscopy (AFM, Multimode, Bruker) in flow-through experiments. Changes in calcium oxalate morphologies and precipitated phases were observed, as well as the inhibitory effect of citrate on calcium oxalate precipitation, which also lead to stabilization an the amorphous calcium oxalate phase. [1] K.D. Demadis, M. Öner, Inhibitory effects of "green"additives on the crystal growth of sparingly soluble salts, in: J.T. Pearlman (Ed.), Green Chemistry Research Trends, Nova Science Publishers Inc., New York, 2009, pp. 265-287. [2] M. Masár, M. Zuborová, D. Kaniansky, B. Stanislawski, Determination of oxalate in beer by zone electrophoresis on a chip with conductivity detection, J. Sep. Sci. 26 (2003) 647-652. [3] Chutipongtanate S, Chaiyarit S, Thongboonkerd V. Citrate, not phosphate, can dissolve calcium oxalate monohydrate crystals and detach these crystals from renal tubular cells. Eur J Pharmacol 2012;689:219-25. [4] Weaver ML, Qiu SR, Hoyer JR, Casey WH, Nancollas GH, De Yoreo JJ. Inhibition of calcium oxalate monohydrate growth by citrate and the effect of the background electrolyte. J Cryst Growth 2007;306:135-45.

Engineering calcium oxalate crystal formation in Arabidopsis

USDA-ARS?s Scientific Manuscript database

Many plants accumulate crystals of calcium oxalate. Just how these crystals form remains unknown. To gain insight into the mechanisms regulating calcium oxalate crystal formation, a crystal engineering approach was initiated utilizing the non-crystal accumulating plant, Arabidopsis. The success of t...

Enhanced Nitrogen Availability in Karst Ecosystems by Oxalic Acid Release in the Rhizosphere

PubMed Central

Pan, Fujing; Liang, Yueming; Zhang, Wei; Zhao, Jie; Wang, Kelin

2016-01-01

In karst ecosystems, a high level of CaCO3 enhances the stabilization of soil organic matter (SOM) and causes nitrogen (N) and/or phosphorus (P) limitation in plants. Oxalic acid has been suggested to be involved in the nutrient-acquisition strategy of plants because its addition can temporarily relieve nutrient limitation. Therefore, understanding how oxalic acid drives N availability may help support successful vegetation restoration in the karst ecosystems of southwest China. We tested a model suggested by Clarholm et al. (2015) where oxalate reacts with Ca bridges in SOM, thus exposing previously protected areas to enzymatic attacks in a way that releases N for local uptake. We studied the effects of oxalic acid, microbial biomass carbon (MBC), and β-1,4-N-acetylglucosaminidase (NAG) on potential N mineralization rates in rhizosphere soils of four plant species (two shrubs and two trees) in karst areas. The results showed that rhizosphere soils of shrubs grown on formerly deforested land had significantly lower oxalic acid concentrations and NAG activity than that of trees in a 200-year-old forest. The levels of MBC in rhizosphere soils of shrubs were significantly lower than those of trees in the growing season, but the measure of shrubs and trees were similar in the non-growing season; the potential N mineralization rates showed a reverse pattern. Positive relationships were found among oxalic acid, MBC, NAG activity, and potential N mineralization rates for both shrubs and trees. This indicated that oxalic acid, microbes, and NAG may enhance N availability for acquisition by plants. Path analysis showed that oxalic acid enhanced potential N mineralization rates indirectly through inducing microbes and NAG activities. We found that the exudation of oxalic acid clearly provides an important mechanism that allows plants to enhance nutrient acquisition in karst ecosystems. PMID:27252713

In vitro and in vivo study of effect of lemon juice on urinary lithogenesis.

PubMed

Oussama, Abdelkhalek; Touhami, Mohamed; Mbarki, Mohamed

2005-12-01

The diversity of experimental results obtained in the study of the effect of citrus juice on urinary lithogenicity moved us to study the effect of these substances in vitro and in-vivo. The in-vitro study is based on the turbidimetric method on calcium oxalate crystallization. In vivo, we studied the effect of lemon juice consumption on urinary chemistry and we tested it on calcium oxalate crystallization in natural urine. The formation of crystals is induced by the addition of the oxalate and calcium solution. Optical density (OD) is measured in a closed system at physiological conditions. The effects of the various juices of lemon, was evaluated by the addition of 50 ml of juice. A male volunteer with no history of kidney stone participated in this study, by lemon juice ingestion. The pH, concentration of oxalate, calcium and citrate were determined before and after ingestion and urine was freshly analyzed by microscopy. In synthetic urine, the inhibition rate of calcium oxalate crystallization increases gradually with the lemon juice concentration. In natural urine, we noted that the kinetics of crystallization of calcium oxalate, before and after ingestion of lemon juice, are comparable. In vivo, after ingestion, a small increase in mean urinary pH (from 6.7 +/- 0.1 to 6.9 +/- 0.1) was noted. Indeed, oxalate calcium means and citrate excretion increased during this period with 33.41%, 6.85% and 3.53% respectively. This increase in the oxalate excretion is probably explained by the conversion of the exogenous ascorbic acid contained in the lemon juice. These results show that the lemon juice presents an important inhibitory effect in vitro. The ingestion of the lemon juice seems to dissipate a effect of great quantity of citrates which in turn increases the excretion of oxalates. The presence of these two elements simultaneously: citrate and oxalate compensate for their opposite effect.

Extension of a PBPK model for ethylene glycol and glycolic acid to include the competitive formation and clearance of metabolites associated with kidney toxicity in rats and humans

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

Corley, R.A., E-mail: rick.corley@pnl.gov; Saghir, S.A.; Bartels, M.J.

2011-02-01

A previously developed PBPK model for ethylene glycol and glycolic acid was extended to include glyoxylic acid, oxalic acid, and the precipitation of calcium oxalate that is associated with kidney toxicity in rats and humans. The development and evaluation of the PBPK model was based upon previously published pharmacokinetic studies coupled with measured blood and tissue partition coefficients and rates of in vitro metabolism of glyoxylic acid to oxalic acid, glycine and other metabolites using primary hepatocytes isolated from male Wistar rats and humans. Precipitation of oxalic acid with calcium in the kidneys was assumed to occur only at concentrationsmore » exceeding the thermodynamic solubility product for calcium oxalate. This solubility product can be affected by local concentrations of calcium and other ions that are expressed in the model using an ion activity product estimated from toxicity studies such that calcium oxalate precipitation would be minimal at dietary exposures below the NOAEL for kidney toxicity in the sensitive male Wistar rat. The resulting integrated PBPK predicts that bolus oral or dietary exposures to ethylene glycol would result in typically 1.4-1.6-fold higher peak oxalate levels and 1.6-2-fold higher AUC's for calcium oxalate in kidneys of humans as compared with comparably exposed male Wistar rats over a dose range of 1-1000 mg/kg. The converse (male Wistar rats predicted to have greater oxalate levels in the kidneys than humans) was found for inhalation exposures although no accumulation of calcium oxalate is predicted to occur until exposures are well in excess of the theoretical saturated vapor concentration of 200 mg/m{sup 3}. While the current model is capable of such cross-species, dose, and route-of-exposure comparisons, it also highlights several areas of potential research that will improve confidence in such predictions, especially at low doses relevant for most human exposures.« less

Aluminum Citrate Prevents Renal Injury from Calcium Oxalate Crystal Deposition

PubMed Central

Besenhofer, Lauren M.; Cain, Marie C.; Dunning, Cody

2012-01-01

Calcium oxalate monohydrate crystals are responsible for the kidney injury associated with exposure to ethylene glycol or severe hyperoxaluria. Current treatment strategies target the formation of calcium oxalate but not its interaction with kidney tissue. Because aluminum citrate blocks calcium oxalate binding and toxicity in human kidney cells, it may provide a different therapeutic approach to calcium oxalate-induced injury. Here, we tested the effects of aluminum citrate and sodium citrate in a Wistar rat model of acute high-dose ethylene glycol exposure. Aluminum citrate, but not sodium citrate, attenuated increases in urea nitrogen, creatinine, and the ratio of kidney to body weight in ethylene glycol–treated rats. Compared with ethylene glycol alone, the addition of aluminum citrate significantly increased the urinary excretion of both crystalline calcium and crystalline oxalate and decreased the deposition of crystals in renal tissue. In vitro, aluminum citrate interacted directly with oxalate crystals to inhibit their uptake by proximal tubule cells. These results suggest that treating with aluminum citrate attenuates renal injury in rats with severe ethylene glycol toxicity, apparently by inhibiting calcium oxalate’s interaction with, and retention by, the kidney epithelium. PMID:23138489

Intercomparison of the measurements of oxalic acid in aerosols by gas chromatography and ion chromatography

NASA Astrophysics Data System (ADS)

Kawamura, Kimitaka; Barrie, Leonard A.; Toom-Sauntry, Desiree

2010-12-01

Oxalate, the anion of oxalic acid, is one of the most abundant measurable organic species in atmospheric aerosols. Traditionally, this bifunctional species has been measured by gas chromatography (GC) after derivatization to butyl ester and by ion chromatography (IC) without derivatization. However, there are few published comparisons of the two techniques. Here, we report the results of an intercomparison study for the measurement of oxalic acid in Arctic aerosols (<2.5 μm, n = 82) collected in 1992 using GC and IC. The concentrations of oxalic acid by GC ranged from 6.5-59.1 ng m -3 (av. 26.0 ng m -3, median 26.2 ng m -3) whereas those by IC ranged from 6.6-52.1 ng m -3 (av. 26.6 ng m -3, median 25.4 ng m -3). They showed a good correlation ( r = 0.84) with a slope of 0.96. Thus, observations of oxalate obtained by GC employing dibutyl esters are almost equal to those by IC. Because the accuracy of oxalic acid by GC method largely depends on the method used, it is important to strictly examine the recovery in each study.

Oxalate content of different drinkable dilutions of tea infusions after different brewing times.

PubMed

Lotfi Yagin, Neda; Mahdavi, Reza; Nikniaz, Zeinab

2012-01-01

The aims of this study were to determine the effect of different brewing times and diluting on oxalate content of loose-packed black teas consumed in Tabriz, Iran. The oxalate content of black teas after brewing for 5, 10, 15, 30, 60 minutes was measured in triplicate by enzymatic assay. In order to attain the most acceptable dilution of tea infusions, tea samples which were brewed for 15, 30 and 60 minutes were diluted two (120 ml), three (80 ml) and four (60 ml) times respectively. There was a stepwise increase in oxalate concentrations associated with increased brewing times (P< 0.001) with oxalate contents ranging from 4.4 mg/240 ml for the 5 min to 6.3 mg/240 ml for 60 min brewing times, respectively. There were significant differences between the mean oxalate content of different dilutions after brewing for 15, 30 and 60 minutes (P< 0.001). The oxalate content of Iranian consumed black tea after different brewing times and different dilution was below the recommended levels. Therefore, it seems that consumption of black tea several times per day would not pose significant health risk in kidney stone patients and susceptible individuals.

Oxalate Content of Different Drinkable Dilutions of Tea Infusions after Different Brewing Times

PubMed Central

Lotfi Yagin, Neda; Mahdavi, Reza; Nikniaz, Zeinab

2012-01-01

Background: The aims of this study were to determine the effect of different brewing times and diluting on oxalate content of loose-packed black teas consumed in Tabriz, Iran. Methods: The oxalate content of black teas after brewing for 5, 10, 15, 30, 60 minutes was measured in triplicate by enzymatic assay. In order to attain the most acceptable dilution of tea infusions, tea samples which were brewed for 15, 30 and 60 minutes were diluted two (120 ml), three (80 ml) and four (60 ml) times respectively. Results: There was a stepwise increase in oxalate concentrations associated with increased brewing times (P< 0.001) with oxalate contents ranging from 4.4 mg/240 ml for the 5 min to 6.3 mg/240 ml for 60 min brewing times, respectively. There were significant differences between the mean oxalate content of different dilutions after brewing for 15, 30 and 60 minutes (P< 0.001). Conclusion: The oxalate content of Iranian consumed black tea after different brewing times and different dilution was below the recommended levels. Therefore, it seems that consumption of black tea several times per day would not pose significant health risk in kidney stone patients and susceptible individuals. PMID:24688937

Colorimetric sensing of oxalate based on its inhibitory effect on the reaction of Fe (III) with curcumin nanoparticles

NASA Astrophysics Data System (ADS)

Pourreza, Nahid; Lotfizadeh, Neda; Golmohammadi, Hamed

2018-03-01

In this research, a new colorimetric method for the determination of oxalate using curcumin nanoparticles (CURNs) in the presence Fe (III) is introduced. The method is based on the inhibitory effect of oxalate ion on the reaction of (CURNs) with Fe (III) in acidic media. This reaction was monitored by measuring the increase in absorbance of CURNs-Fe3 + complex in the presence of oxalate ion at 427 nm. The effect of different parameters such as the pH of the sample solution, concentration of Fe (III), concentration of CURNs and the reaction time was examined and optimized. Under optimum experimental conditions, the absorption intensity was linear with the concentration of oxalate in the range of 0.15 to 1.70 μg mL- 1. The limit of detection (LOD) was 0.077 μg mL- 1 and the relative standard deviations (RSD) for 8 replicate measurements of 0.40 and 1.05 μg mL- 1 of oxalate were 4.20% and 2.74%, respectively. The developed method was successfully employed to the determination of oxalate in water, food and urine samples with satisfactory results.

An Ru(II)-Fe(III) bimetallic complex as a multifunctional device for detecting, signal amplifying, and degrading oxalate.

PubMed

Chow, Cheuk-Fai; Ho, Pui-Yu; Gong, Cheng-Bin

2014-09-07

A tetranuclear bimetallic complex, [Ru(II)((t)Bubpy)(CN)4]2-[Fe(III)(H2O)3Cl]2·8H2O (1) has been synthesized and characterized. It was found to be a multifunctional device that can detect, signal amplify, and degrade an organic pollutant, oxalate. Results of the chemosensing studies of 1 toward common anions show that only oxalate selectively induces naked-eye colorimetric and luminometric responses with method detection limits down to 78.7 and 5.5 ppm, respectively from 1. Meanwhile, results of the photo-degradation studies of 1 toward oxalate show that the dissolved organic carbon content of oxalate decreased and reached complete mineralization into CO2 within 6 hours. Complex 1 was also found as the catalyst that amplified the detection signal toward oxalate. Through the photoassisted Fenton reaction by 1, methyl orange, an additional coloring agent, could be degraded so that the visual detection limit of 1 toward oxalate was magnified 50 times from 100 to 2 ppm. The detection, degradation, mineralization and signal amplification were found applicable in real water bodies such as river, pond and underground water with excellent recoveries and relative standard deviation.

Prenatal stress-induced increases in hippocampal von Willebrand factor expression are prevented by concurrent prenatal escitalopram

PubMed Central

Neigh, Gretchen N.; Nemeth, Christina L; Kelly, Sean D.; Hardy, Emily E.; Bourke, Chase; Stowe, Zachary N.; Owens, Michael J.

2016-01-01

Prenatal stress has been linked to deficits in neurological function including deficient social behavior, alterations in learning and memory, impaired stress regulation, and susceptibility to adult disease. In addition, prenatal environment is known to alter cardiovascular health; however, limited information is available regarding the cerebrovascular consequences of prenatal stress exposure. Vascular disturbances late in life may lead to cerebral hypoperfusion which is linked to a variety of neurodegenerative and psychiatric diseases. The known impact of cerebrovascular compromise on neuronal function and behavior highlights the importance of characterizing the impact of stress on not just neurons and glia, but also cerebrovasculature. Von Willebrand factor has previously been shown to be impacted by prenatal stress and is predictive of cerebrovascular health. Here we assess the impact of prenatal stress on von Willebrand factor and related angiogenic factors. Furthermore, we assess the potential protective effects of concurrent anti-depressant treatment during in utero stress exposure on the assessed cerebrovascular endpoints. Prenatal stress augmented expression of von Willebrand factor which was prevented by concurrent in utero escitalopram treatment. The functional implications of this increase in von Willebrand factor remain elusive, but the presented data demonstrate that although prenatal stress did not independently impact total vascularization, exposure to chronic stress in adulthood decreased blood vessel length. In addition, the current study demonstrates that production of reactive oxygen species in the hippocampus is decreased by prenatal exposure to escitalopram. Collectively, these findings demonstrate that the prenatal experience can cause complex changes in adult cerebral vascular structure and function. PMID:27422674

Association analysis for oxalate concentration in spinach

USDA-ARS?s Scientific Manuscript database

Screening and breeding low-oxalate germplasm is a major objective in spinach breeding. This research aims to conduct association analysis and identify SNP markers associated with oxalate concentration in spinach germplasm. A total of 310 spinach genotypes including 300 USDA germplasm accessions and ...

Classroom Determination of Trace Organic Substances by Catalytic Methods.

ERIC Educational Resources Information Center

Wenck, Helmut; And Others

1988-01-01

Describes three trace determinations of organic substances utilizing a spectrophotometer. Provides procedures and absorbance wavelengths for determining acetonitrile, oxalic acid, and oxalic acid in human serum. Explores the role of acetonitrile and oxalic acid as catalysts in their respective reactions. (ML)

Structural variability in neptunium(V) oxalate compounds: synthesis and structural characterization of Na2NpO2(C2O4)OH.H2O.

PubMed

Bean, Amanda C; Garcia, Eduardo; Scott, Brian L; Runde, Wolfgang

2004-10-04

Reaction of a (237)Np(V) stock solution in the presence of oxalic acid, calcium chloride, and sodium hydroxide under hydrothermal conditions produces single crystals of a neptunium(V) oxalate, Na(2)NpO(2)(C(2)O(4))OH.H(2)O. The structure consists of one-dimensional chains running down the a axis and is the first example of a neptunium(V) oxalate compound containing hydroxide anions.

Real-time monitoring of the oxalate decarboxylase reaction and probing hydron exchange in the product, formate, using fourier transform infrared spectroscopy.

PubMed

Muthusamy, Mylrajan; Burrell, Matthew R; Thorneley, Roger N F; Bornemann, Stephen

2006-09-05

Oxalate decarboxylase converts oxalate to formate and carbon dioxide and uses dioxygen as a cofactor despite the reaction involving no net redox change. We have successfully used Fourier transform infrared spectroscopy to monitor in real time both substrate consumption and product formation for the first time. The assignment of the peaks was confirmed using [(13)C]oxalate as the substrate. The K(m) for oxalate determined using this assay was 3.8-fold lower than that estimated from a stopped assay. The infrared assay was also capable of distinguishing between oxalate decarboxylase and oxalate oxidase activity by the lack of formate being produced by the latter. In D(2)O, the product with oxalate decarboxylase was C-deuterio formate rather than formate, showing that the source of the hydron was solvent as expected. Large solvent deuterium kinetic isotope effects were observed on V(max) (7.1 +/- 0.3), K(m) for oxalate (3.9 +/- 0.9), and k(cat)/K(m) (1.8 +/- 0.4) indicative of a proton transfer event during a rate-limiting step. Semiempirical quantum mechanical calculations on the stability of formate-derived species gave an indication of the stability and nature of a likely enzyme-bound formyl radical catalytic intermediate. The capability of the enzyme to bind formate under conditions in which the enzyme is known to be active was determined by electron paramagnetic resonance. However, no enzyme-catalyzed exchange of the C-hydron of formate was observed using the infrared assay, suggesting that a formyl radical intermediate is not accessible in the reverse reaction. This restricts the formation of potentially harmful radical intermediates to the forward reaction.

Microorganisms and calcium oxalate stone disease.

PubMed

Goldfarb, David S

2004-01-01

Microorganisms may have a role in the pathogenesis and prevention of kidney stones. The subjects of this review include nanobacteria, Oxalobacter formigenes, and lactic acid bacteria. Not reviewed here is the well-described role of infections of the urinary tract with Proteus species and other urease-producing organisms associated with struvite stone formation. Nanobacteria have been proposed to be very small (0.08-0.5 nm), ubiquitous organisms that could play a role in stone formation. The theory is that nanobacteria can nucleate carbonate apatite on their surfaces and thereby provide the nidus for stone formation. However, their existence remains uncertain and many investigators are openly skeptical. Recent investigations suggest that they are artifacts, and not actually living organisms, but their proponents continue to study them. O. formigenes is an obligate anaerobe which may be important in the prevention of stone formation. Its sole substrate for generation of ATP is oxalate. It may thereby metabolize its human host's dietary oxalate and diminish intestinal absorption and subsequent urinary excretion of oxalate. There is evidence that the organism's absence, perhaps sometimes due to courses of antibiotics, may be a cause of hyperoxaluria and stone formation. In early investigations, patients not colonized with the organism can be recolonized. Urinary oxalate can be diminished by accompanying an oxalate-containing meal with the organism. One study demonstrated that a preparation of lactic acid bacteria successfully reduced urinary oxalate excretion in 6 patients with calcium oxalate stones and hyperoxaluria. The mechanism of this effect is uncertain since these bacteria lacked the gene possessed by O. formigenes which codes for that organism's oxalate uptake mechanism. The author is currently completing a small randomized controlled clinical trial with this preparation in calcium stone-forming patients with idiopathic hyperoxaluria. Copyright (c) 2004 S. Karger AG, Basel.

Secondary formation of oxalic acid and related organic species from biogenic sources in a larch forest at the northern slope of Mt. Fuji

NASA Astrophysics Data System (ADS)

Mochizuki, Tomoki; Kawamura, Kimitaka; Miyazaki, Yuzo; Wada, Ryuichi; Takahashi, Yoshiyuki; Saigusa, Nobuko; Tani, Akira

2017-10-01

To better understand the formation of water-soluble organic aerosols in the forest atmosphere, we measured low molecular weight (LMW) dicarboxylic acids, oxocarboxylic acids, α-dicarbonyls, unsaturated fatty acids (UFAs), and water-soluble organic carbon (WSOC) in aerosols from a Larix kaempferi forest located at the northern slope of Mt. Fuji, Japan, in summer 2012. Concentrations of dicarboxylic acids, oxocarboxylic acids, α-dicarbonyls, and WSOC showed maxima in daytime. Relative abundance of oxalic acid in LMW dicarboxylic acids was on average 52% and its average concentration was 214 ng m-3. We found that diurnal and temporal variations of oxalic acid are different from those of isoprene and α-pinene, whereas biogenic secondary organic aerosols (BSOAs) derived from isoprene and α-pinene showed similar variations with oxalic acid. The mass concentration ratios of oxalic acid/BSOAs were relatively constant, although a large variation in the concentrations of toluene that is an anthropogenic volatile organic compound was observed. These results suggest that formation of oxalic acid is associated with the oxidation of isoprene and α-pinene with O3 and other oxidants in the forest atmosphere. In addition, concentrations of UFAs were observed, for the first time, to decrease dramatically during daytime in the forest. Mass concentration ratios of azelaic acid to UFAs showed a positive correlation with O3, suggesting that UFAs are oxidized to yield azelaic acid, which may be further decomposed to oxalic acid in the forest atmosphere. We found that contributions of oxalic acid to WSOC are significantly high ranging from 3.7 to 9.7% (average 6.0%). This study demonstrates that forest ecosystem is an important source of oxalic acid and other dicarboxylic acids in the atmosphere.

In-cloud oxalate formation in the global troposphere: a 3-D modeling study

NASA Astrophysics Data System (ADS)

Myriokefalitakis, S.; Tsigaridis, K.; Mihalopoulos, N.; Sciare, J.; Nenes, A.; Kawamura, K.; Segers, A.; Kanakidou, M.

2011-06-01

Organic acids attract increasing attention as contributors to atmospheric acidity, secondary organic aerosol mass and aerosol hygroscopicity. Oxalic acid is globally the most abundant dicarboxylic acid, formed via chemical oxidation of gas-phase precursors in the aqueous phase of aerosols and droplets. Its lifecycle and atmospheric global distribution remain highly uncertain and are the focus of this study. The first global spatial and temporal distribution of oxalate, simulated using a state-of-the-art aqueous-phase chemical scheme embedded within the global 3-dimensional chemistry/transport model TM4-ECPL, is here presented. The model accounts for comprehensive gas-phase chemistry and its coupling with major aerosol constituents (including secondary organic aerosol). Model results are consistent with ambient observations of oxalate at rural and remote locations (slope = 1.16 ± 0.14, r2 = 0.36, N = 114) and suggest that aqueous-phase chemistry contributes significantly to the global atmospheric burden of secondary organic aerosol. In TM4-ECPL most oxalate is formed in-cloud and less than 5 % is produced in aerosol water. About 62 % of the oxalate is removed via wet deposition, 30 % by in-cloud reaction with hydroxyl radical, 4 % by in-cloud reaction with nitrate radical and 4 % by dry deposition. The in-cloud global oxalate net chemical production is calculated to be about 21-37 Tg yr-1 with almost 79 % originating from biogenic hydrocarbons, mainly isoprene. This condensed phase net source of oxalate in conjunction with a global mean turnover time against deposition of about 5 days, maintain oxalate's global tropospheric burden of 0.2-0.3 Tg, i.e. 0.05-0.1 Tg-C that is about 5-9 % of model-calculated water soluble organic carbon burden.

Metabolism of Primed, Constant Infusions of [1,2-13C2] Glycine and [1-13C1] Phenylalanine to Urinary Oxalate

PubMed Central

Knight, John; Assimos, Dean G.; Callahan, Michael F.; Holmes, Ross P.

2010-01-01

Objective Experiments in humans and rodents using oral doses of glycine and phenylalanine have suggested that the metabolism of these amino acids contributes to urinary oxalate excretion. To better define this contribution we have examined the primed, constant infusion of [1-13C1] phenylalanine and [1,2-13C2] glycine in the post-absorptive state in healthy adults. Materials/Methods Subjects were infused for 5 hours, collected hourly urines and had blood drawn every 30 minutes. Ion chromatography/mass spectrometry was used to measure [13C] enrichment in urinary oxalate, glycolate and hippurate, and the enrichment of 13C-amino acids in plasma samples was measured by gas chromatography/mass spectrometry. Results Following infusion with either 6 µmoles/kg/hr [1-13C1] phenylalanine or 6 µmoles/kg/hr [1,2-13C2] glycine, no isotopic glycolate or oxalate was detected in urine. Based on the limits of detection of our ion chromatography/mass spectroscopy method, these data indicate that < 0.7% of the urinary oxalate could be derived from phenylalanine catabolism and < 5% from glycine catabolism. Infusions with high levels of [1,2-13C2] glycine, 60 µmoles/kg/hr, increased mean plasma glycine by 29% and the whole body flux of glycine by 72%. Under these conditions glycine contributed 16.0 ± 1.6% and 16.6 ± 3.2% to urinary oxalate and glycolate excretion, respectively. Experiments using cultured hepatoma cells demonstrated that only at supra-physiological levels (>1mM) did glycine and phenylalanine metabolism increase oxalate synthesis. Conclusions These data suggest glycine and phenylalanine metabolism make only minor contributions to oxalate synthesis and urinary oxalate excretion. PMID:21036374

Hydroxyproline metabolism in mouse models of primary hyperoxaluria

PubMed Central

Holmes, Ross P.; Cramer, Scott D.; Takayama, Tatsuya; Salido, Eduardo

2012-01-01

Primary hyperoxaluria type 1 (PH1) and type 2 (PH2) are rare genetic diseases that result from deficiencies in glyoxylate metabolism. The increased oxalate synthesis that occurs can lead to kidney stone formation, deposition of calcium oxalate in the kidney and other tissues, and renal failure. Hydroxyproline (Hyp) catabolism, which occurs mainly in the liver and kidney, is a prominent source of glyoxylate and could account for a significant portion of the oxalate produced in PH. To determine the sensitivity of mouse models of PH1 and PH2 to Hyp-derived oxalate, animals were fed diets containing 1% Hyp. Urinary excretions of glycolate and oxalate were used to monitor Hyp catabolism and the kidneys were examined to assess pathological changes. Both strains of knockout (KO) mice excreted more oxalate than wild-type (WT) animals with Hyp feeding. After 4 wk of Hyp feeding, all mice deficient in glyoxylate reductase/hydroxypyruvate reductase (GRHPR KO) developed severe nephrocalcinosis in contrast to animals deficient in alanine-glyoxylate aminotransferase (AGXT KO) where nephrocalcinosis was milder and with a lower frequency. Plasma cystatin C measurements over 4-wk Hyp feeding indicated no significant loss of renal function in WT and AGXT KO animals, and significant and severe loss of renal function in GRHPR KO animals after 2 and 4 wk, respectively. These data suggest that GRHPR activity may be vital in the kidney for limiting the conversion of Hyp-derived glyoxylate to oxalate. As Hyp catabolism may make a major contribution to the oxalate produced in PH patients, Hyp feeding in these mouse models should be useful in understanding the mechanisms associated with calcium oxalate deposition in the kidney. PMID:22189945

Chronic escitalopram treatment attenuated the accelerated rapid eye movement sleep transitions after selective rapid eye movement sleep deprivation: a model-based analysis using Markov chains.

PubMed

Kostyalik, Diána; Vas, Szilvia; Kátai, Zita; Kitka, Tamás; Gyertyán, István; Bagdy, Gyorgy; Tóthfalusi, László

2014-11-19

Shortened rapid eye movement (REM) sleep latency and increased REM sleep amount are presumed biological markers of depression. These sleep alterations are also observable in several animal models of depression as well as during the rebound sleep after selective REM sleep deprivation (RD). Furthermore, REM sleep fragmentation is typically associated with stress procedures and anxiety. The selective serotonin reuptake inhibitor (SSRI) antidepressants reduce REM sleep time and increase REM latency after acute dosing in normal condition and even during REM rebound following RD. However, their therapeutic outcome evolves only after weeks of treatment, and the effects of chronic treatment in REM-deprived animals have not been studied yet. Chronic escitalopram- (10 mg/kg/day, osmotic minipump for 24 days) or vehicle-treated rats were subjected to a 3-day-long RD on day 21 using the flower pot procedure or kept in home cage. On day 24, fronto-parietal electroencephalogram, electromyogram and motility were recorded in the first 2 h of the passive phase. The observed sleep patterns were characterized applying standard sleep metrics, by modelling the transitions between sleep phases using Markov chains and by spectral analysis. Based on Markov chain analysis, chronic escitalopram treatment attenuated the REM sleep fragmentation [accelerated transition rates between REM and non-REM (NREM) stages, decreased REM sleep residence time between two transitions] during the rebound sleep. Additionally, the antidepressant avoided the frequent awakenings during the first 30 min of recovery period. The spectral analysis showed that the SSRI prevented the RD-caused elevation in theta (5-9 Hz) power during slow-wave sleep. Conversely, based on the aggregate sleep metrics, escitalopram had only moderate effects and it did not significantly attenuate the REM rebound after RD. In conclusion, chronic SSRI treatment is capable of reducing several effects on sleep which might be the consequence of the sub-chronic stress caused by the flower pot method. These data might support the antidepressant activity of SSRIs, and may allude that investigating the rebound period following the flower pot protocol could be useful to detect antidepressant drug response. Markov analysis is a suitable method to study the sleep pattern.

Dissolution of Simulated and Radioactive Savannah River Site High-Level Waste Sludges with Oxalic Acid & Citric Acid Solutions

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

STALLINGS, MARY

This report presents findings from tests investigating the dissolution of simulated and radioactive Savannah River Site sludges with 4 per cent oxalic acid and mixtures of oxalic and citric acid previously recommended by a Russian team from the Khlopin Radium Institute and the Mining and Chemical Combine (MCC). Testing also included characterization of the simulated and radioactive waste sludges. Testing results showed the following: Dissolution of simulated HM and PUREX sludges with oxalic and citric acid mixtures at SRTC confirmed general trends reported previously by Russian testing. Unlike the previous Russian testing six sequential contacts of a mixture of oxalicmore » acid citric acids at a 2:1 ratio (v/w) of acid to sludge did not produce complete dissolution of simulated HM and PUREX sludges. We observed that increased sludge dissolution occurred at a higher acid to sludge ratio, 50:1 (v/w), compared to the recommended ratio of 2:1 (v/w). We observed much lower dissolution of aluminum in a simulated HM sludge by sodium hydroxide leaching. We attribute the low aluminum dissolution in caustic to the high fraction of boehmite present in the simulated sludge. Dissolution of HLW sludges with 4 per cent oxalic acid and oxalic/citric acid followed general trends observed with simulated sludges. The limited testing suggests that a mixture of oxalic and citric acids is more efficient for dissolving HM and PUREX sludges and provides a more homogeneous dissolution of HM sludge than oxalic acid alone. Dissolution of HLW sludges in oxalic and oxalic/citric acid mixtures produced residual sludge solids that measured at higher neutron poison to equivalent 235U weight ratios than that in the untreated sludge solids. This finding suggests that residual solids do not present an increased nuclear criticality safety risk. Generally the neutron poison to equivalent 235U weight ratios of the acid solutions containing dissolved sludge components are lower than those in the untreated sludge solids. We recommend that these results be evaluated further to determine if these solutions contain sufficient neutron poisons. We observed low general corrosion rates in tests in which carbon steel coupons were contacted with solutions of oxalic acid, citric acid and mixtures of oxalic and citric acids. Wall thinning can be minimized by maintaining short contact times with these acid solutions. We recommend additional testing with oxalic and oxalic/citric acid mixtures to measure dissolution performance of sludges that have not been previously dried. This testing should include tests to clearly ascertain the effects of total acid strength and metal complexation on dissolution performance. Further work should also evaluate the downstream impacts of citric acid on the SRS High-Level Waste System (e.g., radiochemical separations in the Salt Waste Processing Facility and addition of organic carbon in the Saltstone and Defense Waste Processing facilities).« less

TREATMENT TANK CORROSION STUDIES FOR THE ENHANCED CHEMICAL CLEANING PROCESS

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

Wiersma, B.

2011-08-24

Radioactive waste is stored in high level waste tanks on the Savannah River Site (SRS). Savannah River Remediation (SRR) is aggressively seeking to close the non-compliant Type I and II waste tanks. The removal of sludge (i.e., metal oxide) heels from the tank is the final stage in the waste removal process. The Enhanced Chemical Cleaning (ECC) process is being developed and investigated by SRR to aid in Savannah River Site (SRS) High-Level Waste (HLW) as an option for sludge heel removal. Corrosion rate data for carbon steel exposed to the ECC treatment tank environment was obtained to evaluate themore » degree of corrosion that occurs. These tests were also designed to determine the effect of various environmental variables such as temperature, agitation and sludge slurry type on the corrosion behavior of carbon steel. Coupon tests were performed to estimate the corrosion rate during the ECC process, as well as determine any susceptibility to localized corrosion. Electrochemical studies were performed to develop a better understanding of the corrosion mechanism. The tests were performed in 1 wt.% and 2.5 wt.% oxalic acid with HM and PUREX sludge simulants. The following results and conclusions were made based on this testing: (1) In 1 wt.% oxalic acid with a sludge simulant, carbon steel corroded at a rate of less than 25 mpy within the temperature and agitation levels of the test. No susceptibility to localized corrosion was observed. (2) In 2.5 wt.% oxalic acid with a sludge simulant, the carbon steel corrosion rates ranged between 15 and 88 mpy. The most severe corrosion was observed at 75 C in the HM/2.5 wt.% oxalic acid simulant. Pitting and general corrosion increased with the agitation level at this condition. No pitting and lower general corrosion rates were observed with the PUREX/2.5 wt.% oxalic acid simulant. The electrochemical and coupon tests both indicated that carbon steel is more susceptible to localized corrosion in the HM/oxalic acid environment than in the PUREX/oxalic acid environment. (3) The corrosion rates for PUREX/8 wt.% oxalic acid were greater than or equal to those observed for the PUREX/2.5 wt.% oxalic acid. No localized corrosion was observed in the tests with the 8 wt.% oxalic acid. Testing with HM/8 wt.% oxalic acid simulant was not performed. Thus, a comparison with the results with 2.5 wt.% oxalic acid, where the corrosion rate was 88 mpy and localized corrosion was observed at 75 C, cannot be made. (4) The corrosion rates in 1 and 2.5 wt.% oxalic acid solutions were temperature dependent: (a) At 50 C, the corrosion rates ranged between 90 to 140 mpy over the 30 day test period. The corrosion rates were higher under stagnant conditions. (b) At 75 C, the initial corrosion rates were as high as 300 mpy during the first day of exposure. The corrosion rates increased with agitation. However, once the passive ferrous oxalate film formed, the corrosion rate decreased dramatically to less than 20 mpy over the 30 day test period. This rate was independent of agitation. (5) Electrochemical testing indicated that for oxalic acid/sludge simulant mixtures the cathodic reaction has transport controlled reaction kinetics. The literature suggests that the dissolution of the sludge produces a di-oxalatoferrate ion that is reduced at the cathodic sites. The cathodic reaction does not appear to involve hydrogen evolution. On the other hand, electrochemical tests demonstrated that the cathodic reaction for corrosion of carbon steel in pure oxalic acid involves hydrogen evolution. (6) Agitation of the oxalic acid/sludge simulant mixtures typically resulted in a higher corrosion rates for both acid concentrations. The transport of the ferrous ion away from the metal surface results in a less protective ferrous oxalate film. (7) A mercury containing species along with aluminum, silicon and iron oxides was observed on the interior of the pits formed in the HM/2.5 wt.% oxalic acid simulant at 75 C. The pitting rates in the agitated and non-agitated solution were 2 mils/day and 1 mil/day, respectively. A mechanism by which the mercury interacts with the aluminum and silicon oxides in this simulant to accelerate corrosion was proposed.« less

Effect of calcium oxalate on the photocatalytic degradation of Orange II on ZnO surface

NASA Astrophysics Data System (ADS)

Bassaid, S.; Ziane, B.; Badaoui, M.; Chaib, M.; Robert, D.

2013-06-01

The photocatalytic degradation of aqueous solution of Orange II, has been investigated in the presence of ZnO catalyst with calcium oxalate as sacrificial agent. This study demonstrated that the performance of ZnO photocatalyst can be improved by addition of calcium oxalate. Results show that adsorption is an important parameter controlling the degradation phenomena. Indeed, the added oxalate causes a drop in the pH medium, what causes a better adsorption of Orange II on the ZnO surface. The effect of calcium oxalate is to increase the concentration of superoxides (O{2/·-}) and hydroperoxides (HO2·) radicals, which are key intermediaries in the mechanism of photodegradation because of their powerful force of oxidation.

Hydrothermal growth of cross-linked hyperbranched copper dendrites using copper oxalate complex

NASA Astrophysics Data System (ADS)

Truong, Quang Duc; Kakihana, Masato

2012-06-01

A facile and surfactant-free approach has been developed for the synthesis of cross-linked hyperbranched copper dendrites using copper oxalate complex as a precursor and oxalic acid as a reducing and structure-directing agent. The synthesized particles are composed of highly branched nanostructures with unusual cross-linked hierarchical networks. The formation of copper dendrites can be explained in view of both diffusion control and aggregation-based growth model accompanied by the chelation-assisted assembly. Oxalic acid was found to play dual roles as reducing and structure-directing agent based on the investigation results. The understanding on the crystal growth and the roles of oxalic acid provides clear insight into the formation mechanism of hyperbranched metal dendrites.

Calcium oxalate syntheses in a solution containing glucose by the atmospheric pressure plasma irradiation

NASA Astrophysics Data System (ADS)

Kurake, Naoyuki; Tanaka, Hiromasa; Ishikawa, Kenji; Nakamura, Kae; Kajiyama, Hiroaki; Kikkawa, Fumitaka; Mizuno, Masaaki; Yamanishi, Yoko; Hori, Masaru

2016-09-01

The non-equilibrium atmospheric pressure plasma (NEAPP) has been attracted attention because of its characteristic high reactivity even in a low temperature so that various phenomena by the NEAPP such as a sterilization, growth promotion and so forth have been reported around the world. Previously, we reported the NEAPP irradiation generated the calcium oxalate crystals in the medium, which contains 31 kinds of organics and inorganics. The Dulbecco's Modified Eagle Medium (DMEM) which was used in previous study is composed of no oxalate. Interestingly, not only crystallization but also synthesis of the oxalate was occurred by the NEAPP irradiation. Also the crystallization details were analyzed with the X-ray diffraction (XRD). In this study, we have clarified the mechanism on the crystallization due that D-glucose, calcium ion and bicarbonate ions are minimum essential components. The oxalate synthesis was proved by the gas chromatography and mass spectrometer (GC-MS). Finally, we conclude that a supersaturation of oxalic acid synthesized in those 3 species by the NEAPP.

Oxalate minerals on Mars?

NASA Astrophysics Data System (ADS)

Applin, D. M.; Izawa, M. R. M.; Cloutis, E. A.; Goltz, D.; Johnson, J. R.

2015-06-01

Small amounts of unidentified organic compounds have only recently been inferred on Mars despite strong reasons to expect significant concentrations and decades of searching. Based on X-ray diffraction and reflectance spectroscopic analyses we show that solid oxalic acid and its most common mineral salts are stable under the pressure and ultraviolet irradiation environment of the surface of Mars, and could represent a heretofore largely overlooked reservoir of organic carbon in the martian near-surface. In addition to the delivery to Mars by carbonaceous chondrites, oxalate minerals are among the predicted breakdown products of meteoritic organic matter delivered to the martian surface, as well as any endogenic organic carbon reaching the martian surface from the interior. A reinterpretation of pyrolysis experiments from the Viking, Phoenix, and Mars Science Laboratory missions shows that all are consistent with the presence of significant concentrations of oxalate minerals. Oxalate minerals could be important in numerous martian geochemical processes, including acting as a possible nitrogen sink (as ammonium oxalate), and contributing to the formation of “organic” carbonates, methane, and hydroxyl radicals.

Externalization of phosphatidylserine via multidrug resistance 1 (MDR1)/P-glycoprotein in oxalate-treated renal epithelial cells: implications for calcium oxalate urolithiasis.

PubMed

Li, Yu-Hang; Yu, Shi-Liang; Gan, Xiu-Guo; Pan, Shang-Ha; Teng, Yue-Qiu; An, Rui-Hua

2016-02-01

We investigated the possible involvement of multidrug resistance protein 1 P-glycoprotein (MDR1 P-gp) in the oxalate-induced redistribution of phosphatidylserine in renal epithelial cell membranes. Real-time PCR and western blotting were used to examine MDR1 expression in Madin-Darby canine kidney cells at the mRNA and protein levels, respectively, whereas surface-expressed phosphatidylserine was detected by the annexin V-binding assay. Oxalate treatment resulted in increased synthesis of MDR1, which resulted in phosphatidylserine (PS) externalization in the renal epithelial cell membrane. Treatment with the MDR1 inhibitor PSC833 significantly attenuated phosphatidylserine externalization. Transfection of the human MDR1 gene into renal epithelial cells significantly increased PS externalization. To our knowledge, this study is the first to show that oxalate increases the synthesis of MDR1 P-gp, which plays a key role in hyperoxaluria-promoted calcium oxalate urolithiasis by facilitating phosphatidylserine redistribution in renal epithelial cells.

In vitro anti-inflammatory activity of selected oxalate-degrading probiotic bacteria: potential applications in the prevention and treatment of hyperoxaluria.

PubMed

Giardina, Silvana; Scilironi, Cristina; Michelotti, Angela; Samuele, Alberta; Borella, Fabio; Daglia, Maria; Marzatico, Fulvio

2014-03-01

Oxalate (Ox) is a very common component of the human diet, capable to collect in the renal tissue and bind calcium to form calcium oxalate (CaOx) crystals. A supersaturation of CaOx crystal may cause nephrocalcinosis and nephrolithiasis. The inflammation derived from the CaOx crystal accumulation, together with innate or secondary renal alterations, could strongly affect the renal function. In this case a consumption of probiotics with either oxalate-degrading activity at intestinal level and systemic anti-inflammatory activity could be an alternative approach to treat the subjects with excess of urinary oxalate excretion. 11 strains of lactic acid bacteria (Lactobacilli and Bifidobacteria), already included in the list of bacteria safe for the human use, were investigated for their capability to degrade oxalate by mean of RP-HPLC-UV method and modulate inflammation in an in vitro model system based on peripheral blood mononuclear cells. Four promising bacterial strains (Lactobacillus plantarum PBS067, Lactobacillus acidophilus LA-14, Bifidobacterium breve PBS077, Bifidobacterium longum PBS078) were identified as innovative biological tools for the prevention and the therapeutic treatment of hyperoxaluria and the inflammatory events associated to the Ox accumulation. The oxalate-degrading activity of some probiotics and their capability to modulate the release of inflammation mediators could be exploited as a new nutraceutical and therapeutic approach for the treatment of oxalate accumulation and the related inflammatory state. © 2014 Institute of Food Technologists®

Real-Time Studies of Iron Oxalate-Mediated Oxidation of Glycolaldehyde as a Model for Photochemical Aging of Aqueous Tropospheric Aerosols.

PubMed

Thomas, Daniel A; Coggon, Matthew M; Lignell, Hanna; Schilling, Katherine A; Zhang, Xuan; Schwantes, Rebecca H; Flagan, Richard C; Seinfeld, John H; Beauchamp, J L

2016-11-15

The complexation of iron(III) with oxalic acid in aqueous solution yields a strongly absorbing chromophore that undergoes efficient photodissociation to give iron(II) and the carbon dioxide anion radical. Importantly, iron(III) oxalate complexes absorb near-UV radiation (λ > 350 nm), providing a potentially powerful source of oxidants in aqueous tropospheric chemistry. Although this photochemical system has been studied extensively, the mechanistic details associated with its role in the oxidation of dissolved organic matter within aqueous aerosol remain largely unknown. This study utilizes glycolaldehyde as a model organic species to examine the oxidation pathways and evolution of organic aerosol initiated by the photodissociation of aqueous iron(III) oxalate complexes. Hanging droplets (radius 1 mm) containing iron(III), oxalic acid, glycolaldehyde, and ammonium sulfate (pH ∼3) are exposed to irradiation at 365 nm and sampled at discrete time points utilizing field-induced droplet ionization mass spectrometry (FIDI-MS). Glycolaldehyde is found to undergo rapid oxidation to form glyoxal, glycolic acid, and glyoxylic acid, but the formation of high molecular weight oligomers is not observed. For comparison, particle-phase experiments conducted in a laboratory chamber explore the reactive uptake of gas-phase glycolaldehyde onto aqueous seed aerosol containing iron and oxalic acid. The presence of iron oxalate in seed aerosol is found to inhibit aerosol growth. These results suggest that photodissociation of iron(III) oxalate can lead to the formation of volatile oxidation products in tropospheric aqueous aerosols.

Contribution of calcium oxalate to soil-exchangeable calcium

USGS Publications Warehouse

Dauer, Jenny M.; Perakis, Steven S.

2013-01-01

Acid deposition and repeated biomass harvest have decreased soil calcium (Ca) availability in many temperate forests worldwide, yet existing methods for assessing available soil Ca do not fully characterize soil Ca forms. To account for discrepancies in ecosystem Ca budgets, it has been hypothesized that the highly insoluble biomineral Ca oxalate might represent an additional soil Ca pool that is not detected in standard measures of soil-exchangeable Ca. We asked whether several standard method extractants for soil-exchangeable Ca could also access Ca held in Ca oxalate crystals using spike recovery tests in both pure solutions and soil extractions. In solutions of the extractants ammonium chloride, ammonium acetate, and barium chloride, we observed 2% to 104% dissolution of Ca oxalate crystals, with dissolution increasing with both solution molarity and ionic potential of cation extractant. In spike recovery tests using a low-Ca soil, we estimate that 1 M ammonium acetate extraction dissolved sufficient Ca oxalate to contribute an additional 52% to standard measurements of soil-exchangeable Ca. However, in a high-Ca soil, the amount of Ca oxalate spike that would dissolve in 1 M ammonium acetate extraction was difficult to detect against the large pool of exchangeable Ca. We conclude that Ca oxalate can contribute substantially to standard estimates of soil-exchangeable Ca in acid forest soils with low soil-exchangeable Ca. Consequently, measures of exchangeable Ca are unlikely to fully resolve discrepancies in ecosystem Ca mass balance unless the contribution of Ca oxalate to exchangeable Ca is also assessed.

Characterization of Medicago truncatula reduced calcium oxalate crystal mutant alleles

USDA-ARS?s Scientific Manuscript database

Calcium oxalate crystal formation is common in plants. Formation of these crystals has been shown to function in plant defense, calcium regulation, and aluminum tolerance. Although calcium oxalate is common and plays important roles in plant development, our understanding of how these crystals form ...

Characterization of calcium oxalate defective (cod) 3 mutant from Medicago truncatula

USDA-ARS?s Scientific Manuscript database

Many plants invest a considerable amount of resources and energy into the formation of calcium oxalate crystals. Assigned roles for plant crystal formation include functions in defense, calcium regulation, and aluminum tolerance. From a human health standpoint, oxalate present in edible plant tiss...

Plant calcium oxalate crystal formation, function, and its impact on human health

USDA-ARS?s Scientific Manuscript database

Crystals of calcium oxalate have been observed among members from most taxonomic groups of photosynthetic organisms ranging from the smallest algae to the largest trees. The biological roles for calcium oxalate crystal formation in plant growth and development include high capacity calcium regulatio...

Cardiovascular Risk with Non-Steroidal Anti-Inflammatory Drugs: Systematic Review of Population-Based Controlled Observational Studies

PubMed Central

McGettigan, Patricia; Henry, David

2011-01-01

Background Randomised trials have highlighted the cardiovascular risks of non-steroidal anti-inflammatory drugs (NSAIDs) in high doses and sometimes atypical settings. Here, we provide estimates of the comparative risks with individual NSAIDs at typical doses in community settings. Methods and Findings We performed a systematic review of community-based controlled observational studies. We conducted comprehensive literature searches, extracted adjusted relative risk (RR) estimates, and pooled the estimates for major cardiovascular events associated with use of individual NSAIDs, in different doses, and in populations with low and high background risks of cardiovascular events. We also compared individual drugs in pair-wise (within study) analyses, generating ratios of RRs (RRRs). Thirty case-control studies included 184,946 cardiovascular events, and 21 cohort studies described outcomes in >2.7 million exposed individuals. Of the extensively studied drugs (ten or more studies), the highest overall risks were seen with rofecoxib, 1.45 (95% CI 1.33, 1.59), and diclofenac, 1.40 (1.27, 1.55), and the lowest with ibuprofen, 1.18 (1.11, 1.25), and naproxen, 1.09 (1.02, 1.16). In a sub-set of studies, risk was elevated with low doses of rofecoxib, 1.37 (1.20, 1.57), celecoxib, 1.26 (1.09, 1.47), and diclofenac, 1.22 (1.12, 1.33), and rose in each case with higher doses. Ibuprofen risk was seen only with higher doses. Naproxen was risk-neutral at all doses. Of the less studied drugs etoricoxib, 2.05 (1.45, 2.88), etodolac, 1.55 (1.28, 1.87), and indomethacin, 1.30 (1.19, 1.41), had the highest risks. In pair-wise comparisons, etoricoxib had a higher RR than ibuprofen, RRR = 1.68 (99% CI 1.14, 2.49), and naproxen, RRR = 1.75 (1.16, 2.64); etodolac was not significantly different from naproxen and ibuprofen. Naproxen had a significantly lower risk than ibuprofen, RRR = 0.92 (0.87, 0.99). RR estimates were constant with different background risks for cardiovascular disease and rose early in the course of treatment. Conclusions This review suggests that among widely used NSAIDs, naproxen and low-dose ibuprofen are least likely to increase cardiovascular risk. Diclofenac in doses available without prescription elevates risk. The data for etoricoxib were sparse, but in pair-wise comparisons this drug had a significantly higher RR than naproxen or ibuprofen. Indomethacin is an older, rather toxic drug, and the evidence on cardiovascular risk casts doubt on its continued clinical use. Please see later in the article for the Editors' Summary PMID:21980265

The oxalic acid biosynthetic activity of Burkholderia mallei is encoded by a single locus

USDA-ARS?s Scientific Manuscript database

Although it is known that oxalic acid provides a selective advantage to the secreting microbe, our understanding of how this acid is biosynthesized remains incomplete. This study reports the identification, cloning, and partial characterization of the oxalic acid biosynthetic enzyme from the animal ...

Oxalate Synthesis and Pyrolysis: A Colorful Introduction to Stoichiometry

ERIC Educational Resources Information Center

Vannatta, Michael W.; Richards-Babb, Michelle; Sweeney, Robert J.

2010-01-01

Metal oxalate synthesis and pyrolysis provides an opportunity for students to (i) learn stoichiometry, (ii) experience the consequences of proper stoichiometric calculations and experimental techniques, and (iii) be introduced to the relevance of chemistry by highlighting oxalates in context, for example, usages and health effects. At our…

Patterns of calcium oxalate monohydrate crystallization in complex biological systems

NASA Astrophysics Data System (ADS)

Golovanova, O. A.; Korol'kov, V. V.; Kuimova, M. V.

2017-01-01

The paper presents the features of calcium oxalate crystallization in the presence of additives revealed through experimental modeling. The patterns of phase formation are shown for the Ca2+ - C2O4 2- - H2O and Ca2+ - C2O4 2- - PO4 3- - H2O systems with the components and pH of the saline varying over a wide concentrations range. The effect of additives on crystallization of calcium oxalate monohydrate was investigated. It was found that the ionic strength and magnesium ions are inhibitors, and calcium oxalate and hydroxyapatite crystals are catalysts of calcium oxalate monohydrate crystallization. The basic calcium phosphate (apatite) was found to be most thermodynamically stable, which indicates its special role in kidney stone formation since it is found in virtually all stones.

Competitive and Cooperative Effects during Nickel Adsorption to Iron Oxides in the Presence of Oxalate

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

Flynn, Elaine D.; Catalano, Jeffrey G.

Iron oxides are ubiquitous in soils and sediments and play a critical role in the geochemical distribution of trace elements and heavy metals via adsorption and coprecipitation. The presence of organic acids may potentially alter how metals associate with iron oxide minerals through a series of cooperative or competitive processes: solution complexation, ternary surface complexation, and surface site competition. The macroscopic and molecular-scale effects of these processes were investigated for Ni adsorption to hematite and goethite at pH 7 in the presence of oxalate. The addition of this organic acid suppresses Ni uptake on both minerals. Aqueous speciation suggests thatmore » this is dominantly the result of oxalate complexing and solubilizing Ni. Comparison of the Ni surface coverage to the concentration of free (uncomplexed) Ni 2+ in solution suggests that the oxalate also alters Ni adsorption affinity. EXAFS and ATR-FTIR spectroscopies indicate that these changes in binding affinity are due to the formation of Ni–oxalate ternary surface complexes. These observations demonstrate that competition between dissolved oxalate and the mineral surface for Ni overwhelms the enhancement in adsorption associated with ternary complexation. Oxalate thus largely enhances Ni mobility, thereby increasing micronutrient bioavailability and inhibiting contaminant sequestration.« less

Effect of medium pH on chemical selectivity of oxalic acid biosynthesis by Aspergillus niger W78C in submerged batch cultures with sucrose as a carbon source.

PubMed

Walaszczyk, Ewa; Podgórski, Waldemar; Janczar-Smuga, Małgorzata; Dymarska, Ewelina

2018-01-01

The pH of the medium is the key environmental parameter of chemical selectivity of oxalic acid biosynthesis by Aspergillus niger . The activity of the enzyme oxaloacetate hydrolase, which is responsible for decomposition of oxaloacetate to oxalate and acetate inside the cell of the fungus, is highest at pH 6. In the present study, the influence of pH in the range of 3-7 on oxalic acid secretion by A. niger W78C from sucrose was investigated. The highest oxalic acid concentration, 64.3 g dm -3 , was reached in the medium with pH 6. The chemical selectivity of the process was 58.6% because of the presence of citric and gluconic acids in the cultivation broth in the amount of 15.3 and 30.2 g dm -3 , respectively. Both an increase and a decrease of medium pH caused a decrease of oxalic acid concentration. The obtained results confirm that pH 6 of the carbohydrate medium is appropriate for oxalic acid synthesis by A. niger , but the chemical selectivity of the process described in this paper was high in comparison to values reported previously in the literature.

Influence of Oxalate on Ni Fate during Fe(II)-Catalyzed Recrystallization of Hematite and Goethite.

PubMed

Flynn, Elaine D; Catalano, Jeffrey G

2018-06-05

During biogeochemical iron cycling at redox interfaces, dissolved Fe(II) induces the recrystallization of Fe(III) oxides. Oxalate and other organic acids promote dissolution of these minerals and may also induce recrystallization. These processes may redistribute trace metals among the mineral bulk, mineral surface, and aqueous solution. However, the impact of interactions among organic acids, dissolved Fe(II), and iron oxide minerals on trace metal fate in such systems is unclear. The present study thus explores the effect of oxalate on Ni release from and incorporation into hematite and goethite in the absence and presence of Fe(II). When Ni is initially structurally incorporated into the iron oxides, both oxalate and dissolved Fe(II) promote the release of Ni to aqueous solution. When both species are present, their effects on Ni release are synergistic at pH 7 but inhibitory at pH 4, indicating that cooperative and competitive interactions vary with pH. In contrast, oxalate suppresses Ni incorporation into goethite and hematite during Fe(II)-induced recrystallization, decreasing the proportion of Ni substituting in a mineral structure by up to 36%. These observations suggest that at redox interfaces oxalate largely enhances trace metal mobility. In such settings, oxalate, and likely other organic acids, may thus enhance micronutrient availability and inhibit contaminant sequestration.

Sample Results from MCU Solids Outage

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

Peters, T.; Washington, A.; Oji, L.

2014-09-22

Savannah River National Laboratory (SRNL) has received several solid and liquid samples from MCU in an effort to understand and recover from the system outage starting on April 6, 2014. SRNL concludes that the presence of solids in the Salt Solution Feed Tank (SSFT) is the likely root cause for the outage, based upon the following discoveries: A solids sample from the extraction contactor #1 proved to be mostly sodium oxalate; A solids sample from the scrub contactor#1 proved to be mostly sodium oxalate; A solids sample from the Salt Solution Feed Tank (SSFT) proved to be mostly sodium oxalate;more » An archived sample from Tank 49H taken last year was shown to contain a fine precipitate of sodium oxalate; A solids sample from ; A liquid sample from the SSFT was shown to have elevated levels of oxalate anion compared to the expected concentration in the feed. Visual inspection of the SSFT indicated the presence of precipitated or transferred solids, which were likely also in the Salt Solution Receipt Tank (SSRT). The presence of the solids coupled with agitation performed to maintain feed temperature resulted in oxalate solids migration through the MCU system and caused hydraulic issues that resulted in unplanned phase carryover from the extraction into the scrub, and ultimately the strip contactors. Not only did this carryover result in the Strip Effluent (SE) being pushed out of waste acceptance specification, but it resulted in the deposition of solids into several of the contactors. At the same time, extensive deposits of aluminosilicates were found in the drain tube in the extraction contactor #1. However it is not known at this time how the aluminosilicate solids are related to the oxalate solids. The solids were successfully cleaned out of the MCU system. However, future consideration must be given to the exclusion of oxalate solids into the MCU system. There were 53 recommendations for improving operations recently identified. Some additional considerations or additional details are provided below as recommendations. From this point on, IC-Anions analyses of the DSSHT should be part of the monthly routine analysis in order to spot negative trends in the oxalate leaving the MCU system. Care must be taken to monitor the oxalate content to watch for sudden precipitation of oxalate salts in the system; Conduct a study to optimize the cleaning strategy at ARP-MCU through decreasing the concentration or entirely eliminating the oxalic acid; The contents of the SSFT should remain unagitated. Routine visual observation should be maintained to ensure there is not a large buildup of solids. As water with agitation provided sufficient removal of the solids in the feed tank, it should be considered as a good means for dissolving oxalate solids if they are found in the future; Conduct a study to improve prediction of oxalate solubility in salt batch feed materials. As titanium and mercury have been found in various solids in this report, evaluate if either element plays a role in oxalate solubility during processing; Salt batch characterization focuses primarily on characterization and testing of unaltered Tank 21H material; however, non-typical feeds are developed through cleaning, washing, and/or sump transfers. As these solutions are processed through MCU, they may precipitate solids or reduce performance. Salt batch characterization and testing should be expanded to encompass a broader range of feeds that may be processed through ARPMCU.« less

Effect of vitamin C supplements on urinary oxalate and pH in calcium stone-forming patients.

PubMed

Baxmann, Alessandra Calábria; De O G Mendonça, Claudia; Heilberg, Ita Pfeferman

2003-03-01

The contribution of ascorbate to urinary oxalate is controversial. The present study aimed to determine whether urinary oxalate and pH may be affected by vitamin C supplementation in calcium stone-forming patients. Forty-seven adult calcium stone-forming patients received either 1 g (N=23) or 2 g (N=24) of vitamin C supplement for 3 days and 20 healthy subjects received 1 g. A 24-hour urine sample was obtained both before and after vitamin C for calcium, oxalate, magnesium, citrate, sodium, potassium, and creatinine determination. The Tiselius index was used as a calcium oxalate crystallization index. A spot fasting morning urine sample was also obtained to determine the urinary pH before and after vitamin C. Fasting urinary pH did not change after 1 g (5.8 +/- 0.6 vs. 5.8 +/- 0.7) or 2 g vitamin C (5.8 +/- 0.8 vs. 5.8 +/- 0.7). A significant increase in mean urinary oxalate was observed in calcium stone-forming patients receiving either 1 g (50 +/- 16 vs. 31 +/- 12 mg/24 hours) or 2 g (48 +/- 21 vs. 34 +/- 12 mg/24 hours) of vitamin C and in healthy subjects (25 +/- 12 vs. 39 +/- 13 mg/24 hours). A significant increase in mean Tiselius index was observed in calcium stone-forming patients after 1 g (1.43 +/- 0.70 vs. 0.92 +/- 0.65) or 2 g vitamin C (1.61 +/- 1.05 vs. 0.99 +/- 0.55) and in healthy subjects (1.50 +/- 0.69 vs. 0.91 +/- 0.46). Ancillary analyses of spot urine obtained after vitamin C were performed in 15 control subjects in vessels with or without ethylenediaminetetraacetic acid (EDTA) with no difference in urinary oxalate between them (28 +/- 23 vs. 26 +/- 21 mg/L), suggesting that the in vitro conversion of ascorbate to oxalate did not occur. These data suggest that vitamin C supplementation may increase urinary oxalate excretion and the risk of calcium oxalate crystallization in calcium stone-forming patients.

An Oxalyl-CoA Synthetase Is Involved in Oxalate Degradation and Aluminum Tolerance1[OPEN

PubMed Central

Fan, Wei; Xu, Jia Meng; Gong, Yu Long; Jin, Jian Feng; Chen, Wei Wei; Liu, Ling Yu; Hai, Mei Rong

2016-01-01

Acyl Activating Enzyme3 (AAE3) was identified to be involved in the catabolism of oxalate, which is critical for seed development and defense against fungal pathogens. However, the role of AAE3 protein in abiotic stress responses is unknown. Here, we investigated the role of rice bean (Vigna umbellata) VuAAE3 in Al tolerance. Recombinant VuAAE3 protein has specific activity against oxalate, with Km = 121 ± 8.2 µm and Vmax of 7.7 ± 0.88 µmol min−1 mg−1 protein, indicating it functions as an oxalyl-CoA synthetase. VuAAE3-GFP localization suggested that this enzyme is a soluble protein with no specific subcellular localization. Quantitative reverse transcription-PCR and VuAAE3 promoter-GUS reporter analysis showed that the expression induction of VuAAE3 is mainly confined to rice bean root tips. Accumulation of oxalate was induced rapidly by Al stress in rice bean root tips, and exogenous application of oxalate resulted in the inhibition of root elongation and VuAAE3 expression induction, suggesting that oxalate accumulation is involved in Al-induced root growth inhibition. Furthermore, overexpression of VuAAE3 in tobacco (Nicotiana tabacum) resulted in the increase of Al tolerance, which was associated with the decrease of oxalate accumulation. In addition, NtMATE and NtALS3 expression showed no difference between transgenic lines and wild-type plants. Taken together, our results suggest that VuAAE3-dependent turnover of oxalate plays a critical role in Al tolerance mechanisms. PMID:27650448

Biological Control of Meloidogyne incognita by Aspergillus niger F22 Producing Oxalic Acid

PubMed Central

Jang, Ja Yeong; Choi, Yong Ho; Shin, Teak Soo; Kim, Tae Hoon; Shin, Kee-Sun; Park, Hae Woong; Kim, Young Ho; Kim, Hun; Choi, Gyung Ja; Jang, Kyoung Soo; Cha, Byeongjin; Kim, In Seon; Myung, Eul Jae

2016-01-01

Restricted usage of chemical nematicides has led to development of environmentally safe alternatives. A culture filtrate of Aspergillus niger F22 was highly active against Meloidogyne incognita with marked mortality of second-stage juveniles (J2s) and inhibition of egg hatching. The nematicidal component was identified as oxalic acid by organic acid analysis and gas chromatography-mass spectroscopy (GC-MS). Exposure to 2 mmol/L oxalic acid resulted in 100% juvenile mortality at 1 day after treatment and suppressed egg hatching by 95.6% at 7 days after treatment. Oxalic acid showed similar nematicidal activity against M. hapla, but was not highly toxic to Bursaphelenchus xylophilus. The fungus was incubated on solid medium and dried culture was used for preparation of a wettable powder-type (WP) formulation as an active ingredient. Two WP formulations, F22-WP10 (ai 10%) and oxalic acid-WP8 (ai 8%), were prepared using F22 solid culture and oxalic acid. In a field naturally infested with M. incognita, application of a mixture of F22-WP10 + oxalic acid-WP8 at 1,000- and 500-fold dilutions significantly reduced gall formation on the roots of watermelon plants by 58.8 and 70.7%, respectively, compared to the non-treated control. The disease control efficacy of the mixture of F22-WP10 + oxalic acid-WP8 was significantly higher than that of a chemical nematicide, Sunchungtan (ai 30% fosthiazate). These results suggest that A. niger F22 can be used as a microbial nematicide for the control of root-knot nematode disease. PMID:27258452

Biological Control of Meloidogyne incognita by Aspergillus niger F22 Producing Oxalic Acid.

PubMed

Jang, Ja Yeong; Choi, Yong Ho; Shin, Teak Soo; Kim, Tae Hoon; Shin, Kee-Sun; Park, Hae Woong; Kim, Young Ho; Kim, Hun; Choi, Gyung Ja; Jang, Kyoung Soo; Cha, Byeongjin; Kim, In Seon; Myung, Eul Jae; Kim, Jin-Cheol

2016-01-01

Restricted usage of chemical nematicides has led to development of environmentally safe alternatives. A culture filtrate of Aspergillus niger F22 was highly active against Meloidogyne incognita with marked mortality of second-stage juveniles (J2s) and inhibition of egg hatching. The nematicidal component was identified as oxalic acid by organic acid analysis and gas chromatography-mass spectroscopy (GC-MS). Exposure to 2 mmol/L oxalic acid resulted in 100% juvenile mortality at 1 day after treatment and suppressed egg hatching by 95.6% at 7 days after treatment. Oxalic acid showed similar nematicidal activity against M. hapla, but was not highly toxic to Bursaphelenchus xylophilus. The fungus was incubated on solid medium and dried culture was used for preparation of a wettable powder-type (WP) formulation as an active ingredient. Two WP formulations, F22-WP10 (ai 10%) and oxalic acid-WP8 (ai 8%), were prepared using F22 solid culture and oxalic acid. In a field naturally infested with M. incognita, application of a mixture of F22-WP10 + oxalic acid-WP8 at 1,000- and 500-fold dilutions significantly reduced gall formation on the roots of watermelon plants by 58.8 and 70.7%, respectively, compared to the non-treated control. The disease control efficacy of the mixture of F22-WP10 + oxalic acid-WP8 was significantly higher than that of a chemical nematicide, Sunchungtan (ai 30% fosthiazate). These results suggest that A. niger F22 can be used as a microbial nematicide for the control of root-knot nematode disease.

Fungi, bacteria and soil pH: the oxalate-carbonate pathway as a model for metabolic interaction.

PubMed

Martin, Gaëtan; Guggiari, Matteo; Bravo, Daniel; Zopfi, Jakob; Cailleau, Guillaume; Aragno, Michel; Job, Daniel; Verrecchia, Eric; Junier, Pilar

2012-11-01

The oxalate-carbonate pathway involves the oxidation of calcium oxalate to low-magnesium calcite and represents a potential long-term terrestrial sink for atmospheric CO(2). In this pathway, bacterial oxalate degradation is associated with a strong local alkalinization and subsequent carbonate precipitation. In order to test whether this process occurs in soil, the role of bacteria, fungi and calcium oxalate amendments was studied using microcosms. In a model system with sterile soil amended with laboratory cultures of oxalotrophic bacteria and fungi, the addition of calcium oxalate induced a distinct pH shift and led to the final precipitation of calcite. However, the simultaneous presence of bacteria and fungi was essential to drive this pH shift. Growth of both oxalotrophic bacteria and fungi was confirmed by qPCR on the frc (oxalotrophic bacteria) and 16S rRNA genes, and the quantification of ergosterol (active fungal biomass) respectively. The experiment was replicated in microcosms with non-sterilized soil. In this case, the bacterial and fungal contribution to oxalate degradation was evaluated by treatments with specific biocides (cycloheximide and bronopol). Results showed that the autochthonous microflora oxidized calcium oxalate and induced a significant soil alkalinization. Moreover, data confirmed the results from the model soil showing that bacteria are essentially responsible for the pH shift, but require the presence of fungi for their oxalotrophic activity. The combined results highlight that the interaction between bacteria and fungi is essential to drive metabolic processes in complex environments such as soil. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

Laboratory study of the effect of oxalic acid on the cloud condensation nuclei activity of mineral dust aerosol

NASA Astrophysics Data System (ADS)

Gierlus, Kelly M.; Laskina, Olga; Abernathy, Tricia L.; Grassian, Vicki H.

2012-01-01

Dicarboxylic acids, which make up a significant portion of the atmospheric organic aerosol, are emitted directly through biomass burning as well as produced through the oxidation of volatile organic compounds. Oxalic acid, the most abundant of the dicarboxylic acids, has been shown by recent field studies to be present in mineral dust aerosol particles. The presence of these internally mixed organic compounds can alter the water absorption and cloud condensation nuclei (CCN) abilities of mineral particles in the Earth's atmosphere. The University of Iowa's Multi-Analysis Aerosol Reactor System ( MAARS) was used to measure the CCN activity of internally mixed particles that were generated from a mixture of either calcite or polystyrene latex spheres (PSLs) in an aqueous solution of oxalic acid. Although PSL is not a mineral dust component, it is used here as a non-reactive, insoluble particle. CCN measurements indicate that the internally mixed oxalate/calcite particles showed nearly identical CCN activity compared to the original calcite particles whereas oxalic acid/PSL internally mixed particles showed much greater CCN activity compared to PSL particles alone. This difference is due to the reaction of calcite with oxalic acid, which produces a relatively insoluble calcium oxalate coating on the particle surface and not a soluble coating as it does on the PSL particle. Our results suggest that atmospheric processing of mineral dust aerosol through heterogeneous processes will likely depend on the mineralogy and the specific chemistry involved. Increase in the CCN activity by incorporation of oxalic acid are only expected for unreactive insoluble dust particles that form a soluble coating.

Sulfate and thiosulfate inhibit oxalate transport via a dPrestin (Slc26a6)-dependent mechanism in an insect model of calcium oxalate nephrolithiasis.

PubMed

Landry, Greg M; Hirata, Taku; Anderson, Jacob B; Cabrero, Pablo; Gallo, Christopher J R; Dow, Julian A T; Romero, Michael F

2016-01-15

Nephrolithiasis is one of the most common urinary tract disorders, with the majority of kidney stones composed of calcium oxalate (CaOx). Given its prevalence (US occurrence 10%), it is still poorly understood, lacking progress in identifying new therapies because of its complex etiology. Drosophila melanogaster (fruitfly) is a recently developed model of CaOx nephrolithiasis. Effects of sulfate and thiosulfate on crystal formation were investigated using the Drosophila model, as well as electrophysiological effects on both Drosophila (Slc26a5/6; dPrestin) and mouse (mSlc26a6) oxalate transporters utilizing the Xenopus laevis oocyte heterologous expression system. Results indicate that both transport thiosulfate with a much higher affinity than sulfate Additionally, both compounds were effective at decreasing CaOx crystallization when added to the diet. However, these results were not observed when compounds were applied to Malpighian tubules ex vivo. Neither compound affected CaOx crystallization in dPrestin knockdown animals, indicating a role for principal cell-specific dPrestin in luminal oxalate transport. Furthermore, thiosulfate has a higher affinity for dPrestin and mSlc26a6 compared with oxalate These data indicate that thiosulfate's ability to act as a competitive inhibitor of oxalate via dPrestin, can explain the decrease in CaOx crystallization seen in the presence of thiosulfate, but not sulfate. Overall, our findings predict that thiosulfate or oxalate-mimics may be effective as therapeutic competitive inhibitors of CaOx crystallization. Copyright © 2016 the American Physiological Society.

Prophylactic role of phycocyanin: a study of oxalate mediated renal cell injury.

PubMed

Farooq, Shukkur Muhammed; Asokan, Devarajan; Kalaiselvi, Periandavan; Sakthivel, Ramasamy; Varalakshmi, Palaninathan

2004-08-10

Oxalate induced renal calculi formation and the associated renal injury is thought to be caused by free radical mediated mechanisms. An in vivo model was used to investigate the effect of phycocyanin (from Spirulina platensis), a known antioxidant, against calcium oxalate urolithiasis. Male Wistar rats were divided into four groups. Hyperoxaluria was induced in two of these groups by intraperitoneal infusion of sodium oxalate (70 mg/kg) and a pretreatment of phycocyanin (100 mg/kg) as a single oral dosage was given, 1h prior to sodium oxalate infusion. An untreated control and drug control (phycocyanin alone) were also included in the study. We observed that phycocyanin significantly controlled the early biochemical changes in calcium oxalate stone formation. The antiurolithic nature of the drug was evaluated by the assessment of urinary risk factors and light microscopic observation of urinary crystals. Renal tubular damage as divulged by urinary marker enzymes (alkaline phosphatase, acid phosphatase and gamma-glutamyl transferase) and histopathological observations such as decreased tubulointerstitial, tubular dilatation and mononuclear inflammatory cells, indicated that renal damage was minimised in drug-pretreated group. Oxalate levels (P < 0.001) and lipid peroxidation (P < 0.001) in kidney tissue were significantly controlled by drug pretreatment, suggesting the ability of phycocyanin to quench the free radicals, thereby preventing the lipid peroxidation mediated tissue damage and oxalate entry. This accounts for the prevention of CaOx stones. Thus, the present analysis revealed the antioxidant and antiurolithic potential of phycocyanin thereby projecting it as a promising therapeutic agent against renal cell injury associated kidney stone formation.

Influence of calcium oxalate crystal accumulation on the calcium content of seeds from Medicago truncatula

USDA-ARS?s Scientific Manuscript database

Crystals of calcium oxalate often form in cells adjacent to the vascular bundles in the tissues along the xylem stream. This spatial crystal pattern suggests a role for calcium oxalate formation in regulating calcium transport and partitioning to edible organs such as seeds. To investigate this pote...

An oxalyl-CoA synthetase is important for oxalate metabolism in Saccharomyces cerevisiae

USDA-ARS?s Scientific Manuscript database

Although oxalic acid is common in nature, our understanding of the mechanism(s) regulating its turnover remains incomplete. In this study we identify Saccharomyces cerevisiae acyl-activating enzyme 3 (ScAAE3) as an enzyme capable of catalyzing the conversion of oxalate to oxalyl-CoA. Based on our fi...

Degradation of oxalic acid by the mycoparasite Coniothyrium minitans plays an important role in interacting with Sclerotinia sclerotiorum

USDA-ARS?s Scientific Manuscript database

Coniothyrium minitans is a mycoparasite of the phytopathogenic fungus Sclerotinia sclerotiorum. Sclerotinia sclerotiorum produces a virulence factor oxalic acid (OA) which is toxic to plants and also to C. minitans, and C. minitans detoxifies OA by degradation. In this study, two oxalate decarboxyla...

The effects of copper proximity on oxalate production in Fibroporia radiculosa

Treesearch

Katie M. Jenkins; Carol A. Clausen; Frederick Green III

2014-01-01

Copper remains a key component used in wood preservatives available today. However, the observed tolerance of several critical wood rotting organisms continues to be problematic. Tolerance to copper has been linked to the production and accumulation of oxalate, which precipitates copper into insoluble copper-oxalate crystals, thus inactivating copper ions. The purpose...

Insights into the mechanism of copper-tolerance in Fibroporia radiculosa: The biosynthesis of oxalate

Treesearch

Katie Jenkins; Carol A. Clausen; Frederick Green; Susan V. Diehl

2015-01-01

Copper is currently used as the key component in wood preservatives despite the known tolerance of many brown-rot Basidiomycetes. Copper-tolerant fungi, like Fibroporia radiculosa, produce and accumulate high levels of oxalate when exposed to copper. To gain insight into the mechanism of oxalate production, four F. radiculosa...

Determining the biochemical properties of the Oxalate Biosynthetic Component (Obc)1 from Burkholderia mallei

USDA-ARS?s Scientific Manuscript database

Oxalic acid is produced by a variety of organisms ranging from simple microbes to complex animals. This acid has been proposed to fulfill various physiological and pathological functions which vary between organisms. In bacteria from the Burkholderia genus, oxalate secretion has been shown to be quo...

Oxalic acid biosynthesis is encoded by an operon in Burkholderia glumae

USDA-ARS?s Scientific Manuscript database

Although the biosynthesis of oxalic acid is known to occur in a number of bacteria, the mechanism(s) regulating its production remains largely unknown. To date, there is no report on the identification of an oxalic acid biosynthetic pathway gene from bacteria. In an attempt to identify such a gene...

Interaction of Gas Phase Oxalic Acid with Ammonia and its Atmospheric Implications

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

Peng, Xiu-Qiu; Liu, Yi-Rong; Huang, Teng

Oxalic acid is believed to play an important role in the formation and growth of atmospheric organic aerosols. However, as a common organic acid, the understanding of the larger clusters formed by gas phase oxalic acid with multiple ammonia molecules is incomplete. In this work, the structural characteristics and thermodynamics of oxalic acid clusters with up to six ammonia molecules have been investigated at the PW91PW91/6-311++G(3df,3pd) level of theory. We found that oxalic acid forms relatively stable clusters with ammonia molecules, and that ionization events play a key role. The analyses of the thermodynamics and atmospheric relevance indicate that themore » heterodimer (H2C2O4)(NH3) shows an obvious relative concentration in the atmosphere, and thus likely participates in new particle formation. However, with increasing number of ammonia molecules, the concentration of clusters decreases gradually. Additionally, clusters of oxalic acid with ammonia molecules are predicted to form favorably in low temperature conditions and show high Rayleigh scattering intensities.« less

Dissolution kinetics and biodurability of tremolite particles in mimicked lung fluids: Effect of citrate and oxalate

NASA Astrophysics Data System (ADS)

Rozalen, Marisa; Ramos, M. Elena; Huertas, F. Javier; Fiore, Saverio; Gervilla, Fernando

2013-11-01

The effect of citrate and oxalate on tremolite dissolution rate was measured at 37 °C in non-stirred flow-through reactors, using modified Gamble's solutions at pH 4 (macrophages), 7.4 (interstitial fluids) and 5.5 (intermediate check point) containing 0, 0.15, 1.5 and 15 mmol L-1 of citrate or oxalate. The dissolution rates calculated from Si concentration in the output solutions without organic ligands depend on pH, decreasing when the pH increases from -13.00 (pH 4) to -13.35 (pH 7.4) mol g-1 s-1 and following a proton-promoted mechanism. The presence of both ligands enhances dissolution rates at every pH, increasing this effect when the ligand concentration increases. Citrate produces a stronger effect as a catalyst than oxalate, mainly at more acidic pHs and enhances dissolution rates until 20 times for solutions with 15 mmol L-1 citrate. However, at pH 7.4 the effect is lighter and oxalate solutions (15 mmol L-1) only enhances dissolution rates eight times respect to free organic ligand solutions. Dissolution is promoted by the attack to protons and organic ligands to the tremolite surface. Magnesium speciation in oxalate and citrate solutions shows that Mg citrate complexes are more effective than oxalate ones during the alteration of tremolite in magrophages, but this tendency is the opposite for interstitial fluids, being oxalate magnesium complexes stronger. The biodurability estimations show that the destruction of the fibers is faster in acidic conditions (macrophages) than in the neutral solutions (interstitial fluid). At pH 4, both ligands oxalate and citrate reduce the residence time of the fibers with respect to that calculated in absence of ligands. Nevertheless, at pH 7.4 the presence of ligands does not reduce significantly the lifetime of the fibers.

Prenatal exposure to escitalopram and/or stress in rats produces limited effects on endocrine, behavioral, or gene expression measures in adult male rats

PubMed Central

Bourke, Chase H.; Stowe, Zachary N.; Neigh, Gretchen N.; Olson, Darin E.; Owens, Michael J.

2013-01-01

Stress and/or antidepressants during pregnancy have been implicated in a wide range of long-term effects in the offspring. We investigated the long-term effects of prenatal stress and/or clinically relevant antidepressant exposure on male adult offspring in a model of the pharmacotherapy of maternal depression. Female Sprague-Dawley rats were implanted with osmotic minipumps that delivered clinically relevant exposure to the antidepressant escitalopram throughout gestation. Subsequently, pregnant females were exposed on gestational days 10–20 to a chronic unpredictable mild stress paradigm. The male offspring were analyzed in adulthood. Baseline physiological measurements were largely unaltered by prenatal manipulations. Behavioral characterization of the male offspring, with or without pre-exposure to an acute stressor, did not reveal any group differences. Prenatal stress exposure resulted in a faster return towards baseline following the peak response to an acute restraint stressor, but not an airpuff startle stressor, in adulthood. Microarray analysis of the hippocampus and hypothalamus comparing all treatment groups revealed no significantly-altered transcripts. Real time PCR of the hippocampus confirmed that several transcripts in the CRFergic, serotonergic, and neural plasticity pathways were unaffected by prenatal exposures. This stress model of maternal depression and its treatment indicate that escitalopram use and/or stress during pregnancy produced no alterations in our measures of male adult behavior or the transcriptome, however prenatal stress exposure resulted in some evidence for increased glucocorticoid negative feedback following an acute restraint stress. Study design should be carefully considered before implications for human health are ascribed to prenatal exposure to stress or antidepressant medication. PMID:23906943

Prediction of clinical response based on pharmacokinetic/pharmacodynamic models of 5-hydroxytryptamine reuptake inhibitors in mice

PubMed Central

Kreilgaard, M; Smith, D G; Brennum, L T; Sánchez, C

2008-01-01

Background and purpose: Bridging the gap between preclinical research and clinical trials is vital for drug development. Predicting clinically relevant steady-state drug concentrations (Css) in serum from preclinical animal models may facilitate this transition. Here we used a pharmacokinetic/pharmacodynamic (PK/PD) modelling approach to evaluate the predictive validity of 5-hydroxytryptamine (5-HT; serotonin) transporter (SERT) occupancy and 5-hydroxytryptophan (5-HTP)-potentiated behavioral syndrome induced by 5-HT reuptake inhibitor (SRI) antidepressants in mice. Experimental approach: Serum and whole brain drug concentrations, cortical SERT occupancy and 5-HTP-potentiated behavioral syndrome were measured over 6 h after a single subcutaneous injection of escitalopram, paroxetine or sertraline. [3H]2-(2-dimethylaminomethylphenylsulphanyl)-5-methyl-phenylamine ([3H]MADAM) was used to assess SERT occupancy. For PK/PD modelling, an effect-compartment model was applied to collapse the hysteresis and predict the steady-state relationship between drug exposure and PD response. Key results: The predicted Css for escitalopram, paroxetine and sertraline at 80% SERT occupancy in mice are 18 ng mL−1, 18 ng mL−1 and 24 ng mL−1, respectively, with corresponding responses in the 5-HTP behavioral model being between 20–40% of the maximum. Conclusions and implications: Therapeutically effective SERT occupancy for SRIs in depressed patients is approximately 80%, and the corresponding plasma Css are 6–21 ng mL−1, 21-95 ng mL−1 and 20–48 ng mL−1 for escitalopram, paroxetine and sertraline, respectively. Thus, PK/PD modelling using SERT occupancy and 5-HTP-potentiated behavioral syndrome as response markers in mice may be a useful tool to predict clinically relevant plasma Css values. PMID:18552871

Traxoprodil, a selective antagonist of the NR2B subunit of the NMDA receptor, potentiates the antidepressant-like effects of certain antidepressant drugs in the forced swim test in mice.

PubMed

Poleszak, Ewa; Stasiuk, Weronika; Szopa, Aleksandra; Wyska, Elżbieta; Serefko, Anna; Oniszczuk, Anna; Wośko, Sylwia; Świąder, Katarzyna; Wlaź, Piotr

2016-08-01

One of the newest substances, whose antidepressant activity was shown is traxoprodil, which is a selective antagonist of the NR2B subunit of the NMDA receptor. The main goal of the present study was to evaluate the effect of traxoprodil on animals' behavior using the forced swim test (FST), as well as the effect of traxoprodil (10 mg/kg) on the activity of antidepressants, such as imipramine (15 mg/kg), fluoxetine (5 mg/kg), escitalopram (2 mg/kg) and reboxetine (2.5 mg/kg). Serotonergic lesion and experiment using the selective agonists of serotonin receptors 5-HT1A and 5-HT2 was conducted to evaluate the role of the serotonergic system in the antidepressant action of traxoprodil. Brain concentrations of tested agents were determined using HPLC. The results showed that traxoprodil at a dose of 20 and 40 mg/kg exhibited antidepressant activity in the FST and it was not related to changes in animals' locomotor activity. Co-administration of traxoprodil with imipramine, fluoxetine or escitalopram, each in subtherapeutic doses, significantly affected the animals' behavior in the FST and, what is important, these changes were not due to the severity of locomotor activity. The observed effect of traxoprodil is only partially associated with serotonergic system and is independent of the effect on the 5-HT1A and 5-HT2 serotonin receptors. The results of an attempt to assess the nature of the interaction between traxoprodil and the tested drugs show that in the case of joint administration of traxoprodil and fluoxetine, imipramine or escitalopram, there were interactions in the pharmacokinetic phase.

Treatment of anxiety in patients with coronary heart disease: Rationale and design of the UNderstanding the benefits of exercise and escitalopram in anxious patients WIth coroNary heart Disease (UNWIND) randomized clinical trial.

PubMed

Blumenthal, James A; Feger, Bryan J; Smith, Patrick J; Watkins, Lana L; Jiang, Wei; Davidson, Jonathan; Hoffman, Benson M; Ashworth, Megan; Mabe, Stephanie K; Babyak, Michael A; Kraus, William E; Hinderliter, Alan; Sherwood, Andrew

2016-06-01

Anxiety is highly prevalent among patients with coronary heart disease (CHD), and there is growing evidence that high levels of anxiety are associated with worse prognosis. However, few studies have evaluated the efficacy of treating anxiety in CHD patients for reducing symptoms and improving clinical outcomes. Exercise and selective serotonin reuptake inhibitors have been shown to be effective in treating patients with depression, but have not been studied in cardiac patients with high anxiety. The UNWIND trial is a randomized clinical trial of patients with CHD who are at increased risk for adverse events because of comorbid anxiety. One hundred fifty participants with CHD and elevated anxiety symptoms and/or with a diagnosed anxiety disorder will be randomly assigned to 12 weeks of aerobic exercise (3×/wk, 35 min, 70%-85% VO2peak), escitalopram (5-20 mg qd), or placebo. Before and after 12 weeks of treatment, participants will undergo assessments of anxiety symptoms and CHD biomarkers of risk, including measures of inflammation, lipids, hemoglobin A1c, heart rate variability, and vascular endothelial function. Primary outcomes include post-intervention effects on symptoms of anxiety and CHD biomarkers. Secondary outcomes include clinical outcomes (cardiovascular hospitalizations and all-cause death) and measures of quality of life. The UNWIND trial (ClinicalTrials.gov NCT02516332) will evaluate the efficacy of aerobic exercise and escitalopram for improving anxiety symptoms and reducing risk for adverse clinical events in anxious CHD patients. Copyright © 2016 Elsevier Inc. All rights reserved.

The effects of vortioxetine on cognitive dysfunction in patients with inadequate response to current antidepressants in major depressive disorder: A short-term, randomized, double-blind, exploratory study versus escitalopram.

PubMed

Vieta, Eduard; Sluth, Lasse B; Olsen, Christina K

2018-02-01

Major Depressive Disorder (MDD) is a heterogeneous disease characterized by emotional, physical and cognitive symptoms. This study explored the effects of vortioxetine versus escitalopram on outcomes of cognition, functioning and mood symptoms in depressed patients with inadequate response to current antidepressant treatment. In this parallel-group, active-comparator study, adult patients (18-65 years, N = 101) with MDD, with inadequate response to current antidepressant monotherapy, were randomized 1:1 to 8 weeks' double-blind treatment with flexible doses (10-20mg/day) of either vortioxetine or escitalopram. Primary and key secondary efficacy measures were the Digit Symbol Substitution Test (DSST), analyzed using a mixed model for repeated measurements, and the University of San Diego Performance-based Skills Assessment - Brief (UPSA-B), analyzed using analysis of covariance (last observation carried forward method). At week 8, DSST and UPSA-B performance had improved in both treatment groups, with no statistically significant treatment differences. Numerical improvements across measures of cognition, functioning and mood symptoms generally favored vortioxetine. Most adverse events were mild or moderate, with nausea being the most common adverse event. This was an exploratory study with small sample sizes implying limited statistical power. Although this explorative study did not meet primary endpoints, the results confirm vortioxetine in doses of 10-20mg/day as an efficacious and well-tolerated antidepressant switch treatment. The overall direction of numerical effect sizes across cognition endpoints support previous findings that vortioxetine specifically benefits cognitive function in MDD. Copyright © 2017 H Lundbeck A/S. Published by Elsevier B.V. All rights reserved.

Early changes in emotional processing as a marker of clinical response to SSRI treatment in depression.

PubMed

Godlewska, B R; Browning, M; Norbury, R; Cowen, P J; Harmer, C J

2016-11-22

Antidepressant treatment reduces behavioural and neural markers of negative emotional bias early in treatment and has been proposed as a mechanism of antidepressant drug action. Here, we provide a critical test of this hypothesis by assessing whether neural markers of early emotional processing changes predict later clinical response in depression. Thirty-five unmedicated patients with major depression took the selective serotonin re-uptake inhibitor (SSRI), escitalopram (10 mg), over 6 weeks, and were classified as responders (22 patients) versus non-responders (13 patients), based on at least a 50% reduction in symptoms by the end of treatment. The neural response to fearful and happy emotional facial expressions was assessed before and after 7 days of treatment using functional magnetic resonance imaging. Changes in the neural response to these facial cues after 7 days of escitalopram were compared in patients as a function of later clinical response. A sample of healthy controls was also assessed. At baseline, depressed patients showed greater activation to fear versus happy faces than controls in the insula and dorsal anterior cingulate. Depressed patients who went on to respond to the SSRI had a greater reduction in neural activity to fearful versus happy facial expressions after just 7 days of escitalopram across a network of regions including the anterior cingulate, insula, amygdala and thalamus. Mediation analysis confirmed that the direct effect of neural change on symptom response was not mediated by initial changes in depressive symptoms. These results support the hypothesis that early changes in emotional processing with antidepressant treatment are the basis of later clinical improvement. As such, early correction of negative bias may be a key mechanism of antidepressant drug action and a potentially useful predictor of therapeutic response.