- The tegumental allergen-like proteins of Schistosoma mansoni: a biochemical study of SmTAL4-TAL13. [Journal Article]
- MBMol Biochem Parasitol 2018 Feb 14
- Schistosoma mansoni, like other trematodes, expresses a number of unusual calcium binding proteins which consist of an EF-hand domain joined to a dynein light chain-like (DLC-like) domain by a flexib...
Schistosoma mansoni, like other trematodes, expresses a number of unusual calcium binding proteins which consist of an EF-hand domain joined to a dynein light chain-like (DLC-like) domain by a flexible linker. These proteins have been implicated in host immune responses and drug binding. Three members of this protein family from S. mansoni (SmTAL1, SmTAL2 and SmTAL3) have been well characterised biochemically. Here we characterise the remaining family members from this species (SmTAL4-13). All of these proteins form homodimers and all except SmTAL5 bind to calcium and manganese ions. SmTAL9, 10 and 11 also bind to magnesium ions. The antischistosomal drug, praziquantel interacts with SmTAL4, 5 and 8. Some family members also bind to calmodulin antagonists such as chlorpromazine and trifluoperazine. Molecular modelling suggests that all ten proteins adopt similar overall folds with the EF-hand and DLC-like domains folding discretely. Bioinformatics analyses suggest that the proteins may fall into two main categories: (i) those which bind calcium ions reversibly at the second EF-hand and may play a role in signalling (SmTAL1, 2, 8 and 12) and (ii) those which bind calcium ions at the first EF-hand and may play either signalling or structural roles (SmTAL7, 9, 10 and 13). The remaining proteins include those which do not bind calcium ions (SmTAL3 and 5) and three other proteins (SmTAL4, 6 and 11). The roles of these proteins are less clear, but they may also have structural roles.
- Mitochondrial Impairment as a Key Factor for the Lack of Attachment after Cold Storage of Hepatocyte Suspensions. [Journal Article]
- CTCell Transplant 2017; 26(12):1855-1867
- Isolated primary hepatocytes, which are widely used for pharmacological and clinical purposes, usually undergo certain periods of cold storage in suspension during processing. While adherent hepatocy...
Isolated primary hepatocytes, which are widely used for pharmacological and clinical purposes, usually undergo certain periods of cold storage in suspension during processing. While adherent hepatocytes were shown previously to suffer iron-dependent cell death during cold (4 °C) storage and early rewarming, we previously found little iron-dependent hepatocyte death in suspension but severely decreased attachment ability unless iron chelators were added. Here, we focus on the role of mitochondrial impairment in this nonattachment of hepatocyte suspensions. Rat hepatocyte suspensions were stored in a chloride-poor, glycine-containing cold storage solution with and without iron chelators at 4 °C. After 1 wk of cold storage in the basic cold storage solution, cell viability in suspension was unchanged, while cell attachment was decreased by >80%. In the stored cells, a loss of mitochondrial membrane potential (MMP), a decrease in adenosine triphosphate (ATP) content (2 ± 2 nmol/106cells after cold storage, 5 ± 3 nmol/106cells after rewarming vs. control 29 ± 6 nmol/106cells), and a decrease in oxygen consumption (101 ± 59 pmol sec-1per 106cells after rewarming vs. control 232 ± 83 pmol sec-1per 106cells) were observed. Addition of iron chelators to the cold storage solution increased cell attachment to 53% ± 20% and protected against loss of MMP, and cells were able to partially regenerate ATP during rewarming (15 ± 10 nmol/106cells). Increased attachment could also be achieved by addition of the inhibitor combination of mitochondrial permeability transition, trifluoperazine + fructose. Attached hepatocytes displayed normal MMP and mitochondrial morphology. Additional experiments with freshly isolated hepatocytes confirmed that impaired energy production-as elicited by an inhibitor of the respiratory chain, antimycin A-can decrease cell attachment without decreasing viability. Taken together, these results suggest that mitochondrial impairment with subsequent energy deficiency is a key factor for the lack of attachment of cold-stored hepatocyte suspensions.
- Low concentration trifluoperazine promotes proliferation and reduces calcium-dependent apoptosis in glioma cells. [Journal Article]
- SRSci Rep 2018 Jan 18; 8(1):1147
- Glioma patients constitute the greatest percentage of depressed neoplasm patients. These patients often require antidepressant treatment, but the effect of antidepressant drugs on glioma cells requir...
Glioma patients constitute the greatest percentage of depressed neoplasm patients. These patients often require antidepressant treatment, but the effect of antidepressant drugs on glioma cells requires further evaluation. In the present study, we evaluated the effect of trifluoperazine (TFP) on the proliferation and apoptosis of glioma cells. Transcriptomic and bioinformatics analysis results suggested that antidepressant drugs, especially TFP, may upregulate the drug-resistant ability of glioma cells. A low concentration of TFP upregulated the viability of glioma cells. Colony formation and EdU assays confirmed that TFP treatment accelerates glioma cell proliferation, but no significant difference was found in the cell cycle distribution of glioma cells after treatment with TFP or control. Flow cytometry and TUNEL staining results suggested that TFP treatment decreased apoptosis in glioma cells. In addition, TFP treatment downregulated the intracellular Ca2+concentration of glioma cells. In vivo experimental results indicated that TFP treatment promoted proliferation and reduced apoptosis in xenograft tumours in nude mice. Taken together, our results suggest that a low concentration of TFP promotes proliferation and reduces apoptosis in glioma cells both in vitro and in vivo. The potential harmful effects of antidepressant drugs on gliomas require further evaluation before their use in glioma patients.
- A high pressure study of calmodulin-ligand interactions using small-angle X-ray and elastic incoherent neutron scattering. [Journal Article]
- PCPhys Chem Chem Phys 2018 Jan 31; 20(5):3514-3522
- Calmodulin (CaM) is a Ca2+sensor and mediates Ca2+signaling through binding of numerous target ligands. The binding of ligands by Ca2+-saturated CaM (holo-CaM) is governed by attractive hydrophobic a...
Calmodulin (CaM) is a Ca2+sensor and mediates Ca2+signaling through binding of numerous target ligands. The binding of ligands by Ca2+-saturated CaM (holo-CaM) is governed by attractive hydrophobic and electrostatic interactions that are weakened under high pressure in aqueous solutions. Moreover, the potential formation of void volumes upon ligand binding creates a further source of pressure sensitivity. Hence, high pressure is a suitable thermodynamic variable to probe protein-ligand interactions. In this study, we compare the binding of two different ligands to holo-CaM as a function of pressure by using X-ray and neutron scattering techniques. The two ligands are the farnesylated hypervariable region (HVR) of the K-Ras4B protein, which is a natural binding partner of holo-CaM, and the antagonist trifluoperazine (TFP), which is known to inhibit holo-CaM activity. From small-angle X-ray scattering experiments performed up to 3000 bar, we observe a pressure-induced partial unfolding of the free holo-CaM in the absence of ligands, where the two lobes of the dumbbell-shaped protein are slightly swelled. In contrast, upon binding TFP, holo-CaM forms a closed globular conformation, which is pressure stable at least up to 3000 bar. The HVR of K-Ras4B shows a different binding behavior, and the data suggest the dissociation of the holo-CaM/HVR complex under high pressure, probably due to a less dense protein contact of the HVR as compared to TFP. The elastic incoherent neutron scattering experiments corroborate these findings. Below 2000 bar, pressure induces enhanced atomic fluctuations in both holo-CaM/ligand complexes, but those of the holo-CaM/HVR complex seem to be larger. Thus, the inhibition of holo-CaM by TFP is supported by a low-volume ligand binding, albeit this is not associated with a rigidification of the complex structure on the sub-ns Å-scale.
- Management of Morgellons Disease With Low-Dose Trifluoperazine. [Journal Article]
- JDJAMA Dermatol 2018 Feb 01; 154(2):216-218
- Uptake of polyphosphate microparticles in vitro (SaOS-2 and HUVEC cells) followed by an increase of the intracellular ATP pool size. [Journal Article]
- PlosPLoS One 2017; 12(12):e0188977
- Recently two approaches were reported that addressed a vitally important problem in regenerative medicine, i. e. the successful treatment of wounds even under diabetic conditions. Accordingly, these ...
Recently two approaches were reported that addressed a vitally important problem in regenerative medicine, i. e. the successful treatment of wounds even under diabetic conditions. Accordingly, these studies with diabetic rabbits [Sarojini et al. PLoS One 2017, 12(4):e0174899] and diabetic mice [Müller et al. Polymers 2017, 9, 300] identified a novel (potential) target for the acceleration of wound healing in diabetes. Both studies propose a raise of the intracellular metabolic energy status via exogenous administration either of ATP, encapsulated into lipid vesicles, or of polyphosphate (polyP) micro-/nanoparticles. Recently this physiological polymer, polyP, was found to release metabolic energy in form of ATP into both the extra- and also intra-cellular space. In the present work the uptake mechanism of the amorphous polyP microparticles "Ca-polyP-MP" has been described and found to be a clathrin-dependent endocytosis import, based on inhibition studies with the inhibitor trifluoperazine, which blocks the clathrin-dependent endocytosis import. The experiments had been performed with SaOS-2 cells, by studying the uptake and distribution of the electron-dense particles into the cells, and with HUVEC cells, for analysis of the intracellular accumulation of polyP, visualized by fluorescent staining of polyP. Concurrently with the uptake of particular polyP the intracellular ATP level increased as well. In contrast to "Ca-polyP-MP" the soluble polyP, administered as "Na-polyP[Ca2+]", did not cause an increase in the intracellular Ca2+ level, suggesting a different mode of action of these two forms of polyP. Based on existing data on the effect of polyP and ATP on the induction of vascularization during wound repair, both groups (Sarojini et al. and Müller et al.) propose that the acceleration of wound repair is based on an increased metabolic energy supply directly to the regenerating wound area.
- The antipsychotic trifluoperazine reduces marble-burying behavior in mice via D2and 5-HT2Areceptors: Implications for obsessive-compulsive disorder. [Journal Article]
- PBPharmacol Biochem Behav 2018; 165:9-13
- Trifluoperazine, a typical antipsychotic drug, not only antagonizes dopamine D2receptors but also enhances serotonin 5-HT2receptor-mediated behavior. Moreover, trifluoperazine suppresses human purine...
Trifluoperazine, a typical antipsychotic drug, not only antagonizes dopamine D2receptors but also enhances serotonin 5-HT2receptor-mediated behavior. Moreover, trifluoperazine suppresses human purinergic receptor P2X7 responses and calmodulin. However, the effect of trifluoperazine on marble-burying behavior, which has been considered an animal model of obsessive-compulsive disorder (OCD), has not been studied. Here, we examined the effect of trifluoperazine on marble-burying behavior in mice. Oral administration of paroxetine, a selective serotonin reuptake inhibitor, significantly reduced marble-burying behavior without affecting total locomotor activity. Similar results were obtained for trifluoperazine (3mg/kg). The D2receptor agonist, quinpirole (0.03mg/kg, intraperitoneal [i.p.]), and 5-HT2Areceptor antagonist, ketanserin (0.3mg/kg, i.p.), significantly counteracted this reduction of marble-burying behavior by trifluoperazine. These results show that trifluoperazine reduces marble-burying behavior via D2and 5-HT2Areceptors, and may be a useful drug for the treatment of OCD.
- [POISONING BY PSYCHOPHARMACOLOGICAL DRUGS IN AZERBAIJAN: THE RESULTS OF 8-YEAR PROSPECTIVE OBSERVATION]. [Journal Article]
- GMGeorgian Med News 2017; (272):138-144
- Acute poisoning of chemical etiology is a significant global public health problem. The aim of this study was the analysis of the toxicoepidemiological structure of psychopharmacological drugs poison...
Acute poisoning of chemical etiology is a significant global public health problem. The aim of this study was the analysis of the toxicoepidemiological structure of psychopharmacological drugs poisoning in Azerbaijan. We collected and analyzed the data on all cases of acute poisoning by psychopharmacological drugs (codes of categories T42/T43 ICD-10) undergoing inpatient treatment at the Center of Clinical Toxicology in Baku, Azerbaijan in 2009-2016. The total number of patients with acute intoxication by psychopharmacological drugs was 3,413, which was 48.3% of all cases of poisoning by drugs, medicaments and biological substances (T36-T50). The predominance of women was registered in all age groups. 1114 patients or 32.6% were in 15-24 years old age group. The highest percentage of poisonings at category T42 of ICD-10 were benzodiazepine-type drugs (35.8%), and at category T43 - antipsychotic and neuroleptic drugs (19.2%). In the structure of benzodiazepine poisoning, the first and second ranked places belonged to phenazepam (71.0%) and clonazepam - 16.6%. In addition, another 120 cases (5.5%) of poisonings in the T42 cohort were caused by "Z drugs", which have similar therapeutic effect to benzodiazepines (zolpidem and zopiclone). Among the antipsychotic and neuroleptic poisonings, thioridazine, trifluoperazine, levomepromazine, chlorpromazine, and periciazine accounted for 91% of all cases of intoxication in this cohort. Barbiturates, in view of their toxicity and narrow range of therapeutic dosages, now lost their importance as antiepileptic and hypnotic drugs. Only 4.9% of all cases of poisoning, classified under category T42, was due to the use of barbiturates (mainly phenobarbital). Poisonings with iminostilbenes were presented by carbamazepine poisoning only. Most patients in this cohort received this anticonvulsant drug as prescribed by a doctor. Acute intoxications by tricyclic antidepressants in 91.5% were presented by cases of amitriptyline poisoning. Intoxication by serotonin reuptake inhibitors antidepressants, were relatively rare (3.8% of all cases of poisoning in T43). Among the poisonings with butyrophenone and thioxanthene neuroleptics, the first ranked place was occupied by cases of haloperidol poisoning, which accounted for 82.6% in this cohort. In the group of intoxications with other antipsychotic and neuroleptic drugs, the first ranked place belonged to the poisoning with clozapine - a total of 83 cases or 47.2% in cohort. Poisonings by psychopharmacological drugs occupy the first ranking place among poisoning by drugs, medicaments and biological substances (T36-T50). Increased control over the prescription and sale of psychopharmacological drugs, a reduction the number of tablets in one package, as well as increased attention to vulnerable groups of the population could be help to reduce the percentage of these poisonings in Azerbaijan.
- Bioinspired dynamic microcapsules. [Journal Article]
- SMSoft Matter 2017 Dec 20; 14(1):124-131
- There is an increasing interest in bioinspired dynamic materials. Abundant illustrations of protein domains exist in nature, with remarkable ligand binding characteristics and structures that undergo...
There is an increasing interest in bioinspired dynamic materials. Abundant illustrations of protein domains exist in nature, with remarkable ligand binding characteristics and structures that undergo conformational changes. For example, calmodulin (CaM) can have three conformational states, which are the unstructured Apo-state, Ca2+-bound ligand-exposed binding state, and compact ligand-bound state. CaM's mechanical response to biological cues is highly suitable for engineering dynamic materials. The distance between CaM globular terminals in the Ca2+-bound state is 5 nm and in the ligand-bound state is 1.5 nm. CaM's nanoscale conformational changes have been used to develop dynamic hydrogel microspheres that undergo reversible volume changes. The current work presents the fabrication and preliminary results of layer-by-layer (LbL) self-assembled Dynamic MicroCapsules (DynaMicCaps) whose multilayered shell walls are composed of polyelectrolytes and CaM. Quasi-dynamic perfusion results show that the DynaMicCaps undergo drastic volume changes, with up to ∼1500% increase, when exposed to a biochemical ligand trifluoperazine (TFP) at pH 6.3. Under similar test conditions, microcapsules without CaM also underwent volume changes, with only up to ∼290% increase, indicating that CaM's bio-responsiveness was retained within the shell walls of the DynaMicCaps. Furthermore, DynaMicCaps exposed to 0.1 M NaOH underwent volume changes, with only up to ∼580% volume increase. Therefore, DynaMicCaps represent a new class of polyelectrolyte multilayer (PEM) capsules that can potentially be used to release their payload at near physiological pH. With over 200 proteins that undergo marked, well-characterized conformational changes in response to specific biochemical triggers, several other versions of DynaMicCaps can potentially be developed.
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- Zuclopenthixol dihydrochloride for schizophrenia. [Review]
- CDCochrane Database Syst Rev 2017 11 16; 11:CD005474
- CONCLUSIONS: Zuclopenthixol dihydrochloride appears to cause more EPSEs than clozapine, risperidone or perphenazine, but there was no difference in EPSEs when compared to placebo or chlorpromazine. Similar numbers required hypnotics/sedatives when zuclopenthixol dihydrochloride was compared to sulpiride, and similar numbers of reported side-effects were found when its isomers were compared. The other comparisons did not report adverse-effect data.Reported data indicate zuclopenthixol dihydrochloride demonstrates no difference in mental or global states compared to placebo, chlorpromazine, chlorprothixene, clozapine, haloperidol, perphenazine, sulpiride, thiothixene, trifluoperazine, depot and isomers. Zuclopenthixol dihydrochloride, when compared with risperidone, is favoured when assessed using the PANSS in the short term, but not in the medium term.The data extracted from the included studies are mostly equivocal, and very low to low quality, making it difficult to draw firm conclusions. Prescribing practice is unlikely to change based on this meta-analysis. Recommending any particular course of action about side-effect medication other than monitoring, using rating scales and clinical assessment, and prescriptions on a case-by-case basis, is also not possible.There is a need for further studies covering this topic with more antipsychotic comparisons for currently relevant outcomes.