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The long-standing debate that polyphenol secondary metabolites from dietary plants are important nutritional components continues due to compelling evidence for their abilities to ameliorate degenerative conditions including, cancer, neurological disorders and cardiovascular disease. The clinical use of polyphenols is not, however, mainstream as issues regarding poor selectivity, dosage, toxicity and delivery methods are unresolved. The paper by Rieder et al. suggests that the lack of selectivity, at least for the stilbene, resveratrol, may not be a major limiting factor. The present commentary is a critique of this significant finding that is focused on deciding how the use of resveratrol as clinical medicine could be advanced, and how this new information integrates with current knowledge of polyphenol physiological effects. This commentary suggests that the multi-target nature of polyphenols may be translated into reliable therapy using the current systems/network pharmacology approach concerned with developing viable therapeutic agents that achieve specific effects through interactions with a wide array of targets. Linked Article This article is a commentary on Rieder et al., pp. 1244-1258 of BJP 167:6. To view this paper visit http://dx.doi.org/10.1111/j.1476-5381.2012.02063.x [ABSTRACT FROM AUTHOR]

There is a high incidence of psychiatric comorbidity in people with epilepsy ( PWE), particularly depression. The manifold adverse consequences of comorbid depression have been more clearly mapped in recent years. Accordingly, considerable efforts have been made to improve detection and diagnosis, with the result that many PWE are treated with antidepressant drugs, medications with the potential to influence both epilepsy and depression. Exposure to older generations of antidepressants (notably tricyclic antidepressants and bupropion) can increase seizure frequency. However, a growing body of evidence suggests that newer ('second generation') antidepressants, such as selective serotonin reuptake inhibitors or serotonin-noradrenaline reuptake inhibitors, have markedly less effect on excitability and may lead to improvements in epilepsy severity. Although a great deal is known about how antidepressants affect excitability on short time scales in experimental models, little is known about the effects of chronic antidepressant exposure on the underlying processes subsumed under the term 'epileptogenesis': the progressive neurobiological processes by which the non-epileptic brain changes so that it generates spontaneous, recurrent seizures. This paper reviews the literature concerning the influences of antidepressants in PWE and in animal models. The second section describes neurobiological mechanisms implicated in both antidepressant actions and in epileptogenesis, highlighting potential substrates that may mediate any effects of antidepressants on the development and progression of epilepsy. Although much indirect evidence suggests the overall clinical effects of antidepressants on epilepsy itself are beneficial, there are reasons for caution and the need for further research, discussed in the concluding section. [ABSTRACT FROM AUTHOR]

As our knowledge and understanding of the way in which GPCRs operate continues to grow rapidly, many new opportunities are emerging to develop novel therapeutic agents. This themed issue of the British Journal of Pharmacology contains a series of papers that cover recent developments and identify approaches that may help determine future directions. Many of these papers contain material that was presented at the 6th International Molecular Pharmacology of G Protein-Coupled Receptors meeting held at the Monash Institute of Pharmaceutical Sciences in Melbourne Australia in late 2010. LINKED ARTICLES This article is part of a themed section on the Molecular Pharmacology of G Protein-Coupled Receptors (GPCRs). To view the other articles in this section visit . To view the 2010 themed section on the same topic visit [ABSTRACT FROM AUTHOR]

The limitations of traditional anticoagulants, heparin and warfarin, have prompted the development of new anticoagulant drugs for prevention and treatment of both venous and arterial thromboembolism. After a brief review of thrombogenesis and its regulation, this paper focuses on new anticoagulant agents in more advanced stages of clinical testing.British Journal of Pharmacology (2005) 144, 1017-1028. doi:10.1038/sj.bjp.0706153 [ABSTRACT FROM AUTHOR]

Greater scientific understanding of cancer biology, the multistage process of carcinogenesis and tumour responses to conventional and targeted therapeutics have led to the development of combination therapies, for example, chemotherapy with immunotherapy, to achieve long-lasting efficacy and to target metastasis, which is currently the main cause of mortality in many types of cancer (Qin et al., 2020; Schirrmacher, 2019; Wu & Waxman, 2018; Yu et al., 2019). APPROACHES TO IMPROVE OUTCOMES OF EXISTING CANCER TREATMENTS The importance of precision medicine has been incorporated into developing cancer treatments as well as new strategies for decreasing the toxicity of chemotherapeutics and improving therapy outcomes. This article is part of a themed issue on New avenues in cancer prevention and treatment (BJP 75th Anniversary). Moreover, when applied in already developed cancers, nutritional interventions may stop or attenuate cancer progression by targeting cancer hallmarks, such as metastasis (Khadge et al., 2018; Sleeman, 2018). [Extracted from the article]

B Method/Summary of work b : We developed an NBA pipeline that (1) generates patient-specific disease networks by integrating and mapping multifaceted datasets (that include differentially expressed genes from patient's transcriptomic data, the deregulated transcription factors, disease-specific genes from GWAS studies and drug targets of interest) on to the large-scale protein-protein interaction network, (2) identifies key molecules and pathways in the patient-specific disease network and (3) scores each identified potential drug target based on the network connectivity score (that reflects signal propagation) and expression level. J Neurosci; 30: 573 - 582. https://doi.org/10.1523/JNEUROSCI.3295-09.2010 Oral Communications, Tuesday 7th September Oral Communications - Cardiovascular & Respiratory B OC001 b B The effects of allopurinol treatment in early period of monocrotaline-induced rat pulmonary hypertension model b Gokcen Telli SP 1 sp , Inci Kazkayasi SP 1 sp , E. Inci Ergonul SP 2 sp and Serdar Uma SP 1 sp SP 1 sp I Department of Pharmacology, Hacettepe University Faculty of Pharmacy; i SP 2 sp I Republic of Turkey Ministry of Health i B Introduction/Background & aims b : Along with the greater understanding of the pathogenesis of pulmonary hypertension (PH), one of the new treatment approaches is to evaluate the effectiveness of drugs used in diseases with pathologies similar to that of PH [1]. This study investigates the effect of this drug on cell death and proliferative signalling pathways in AML cells in vitro. [Extracted from the article]

Retinoids play important roles in the transcriptional activity of normal, degenerative and tumour cells. Retinoid analogues may be promising therapeutic agents for the treatment of immune disorders as different as type I diabetes and systemic lupus erythematosus. In addition, the use of retinoids in cancer treatment has progressed significantly in the last two decades; thus, numerous retinoid compounds have been synthesized and tested. In this paper, the actual or potential use of retinoids as immunomodulators or tumour-suppressive agents is discussed. [ABSTRACT FROM AUTHOR]

Cyclosporin is an immunosuppressant that has recently been proposed as a treatment to prevent reperfusion injury in acute myocardial infarction (MI). We aimed to determine the overall efficacy of cyclosporin in experimental studies of acute reperfused MI. We conducted a systematic review and stratified meta-analysis of published studies describing the efficacy of cyclosporin in experimental models of acute reperfused MI. We included all in vivo publications of cyclosporin where infarct size was measured. A literature search identified 29 potential studies of which 20 fulfilled the eligibility criteria. In these studies (involving four species of animals), cyclosporin reduced myocardial infarct size by a standardized mean (95% confidence interval) difference of −1.60 (−2.17, −1.03) compared with controls. Cyclosporin failed to demonstrate a convincing benefit in studies involving pigs. Despite this observation, the overall efficacy of cyclosporin did not differ across species ( P= 0.358). The dose of cyclosporin given did not affect final infarct size ( P= 0.203). Funnel plots of these data suggested heterogeneity among the studies. Cyclosporin had variable effects on infarct size compared with placebo. Cyclosporin had no effect on myocardial infarct size in swine, raising a question over the potential cardioprotective effects of cyclosporin in man. [ABSTRACT FROM AUTHOR]

Background and Purpose: Increased glutamatergic innervation of the substantia nigra pars reticulata (SNpr) and pars compacta (SNpc) may contribute to the motor deficits and neurodegeneration, respectively, in Parkinson's disease (PD). This study aimed to establish whether activation of pre-synaptic group III metabotropic glutamate (mGlu) receptors reduced glutamate release in the SN, and provided symptomatic or neuroprotective relief in animal models of PD.Experimental Approach: Broad-spectrum group III mGlu receptor agonists, O-phospho-l-serine (l-SOP) and l-2-amino-4-phosphonobutyrate (l-AP4), were assessed for their ability to inhibit KCl-evoked [(3)H]-d-aspartate release in rat nigral prisms or inhibit KCl-evoked endogenous glutamate release in the SNpr in vivo using microdialysis. Reversal of akinesia in reserpine-treated rats was assessed following intranigral injection of l-SOP and l-AP4. Finally, the neuroprotective effect of 7 days' supra-nigral treatment with l-AP4 was examined in 6-hydroxydopamine (6-OHDA)-lesioned rats.Key Results: l-SOP and l-AP4 inhibited [(3)H]-d-aspartate release by 33 and 44% respectively. These effects were blocked by the selective group III mGlu antagonist (RS)-alpha-cyclopropyl-4-phosphonophenylglycine (CPPG). l-SOP also reduced glutamate release in the SNpr in vivo by 48%. Injection of l-SOP and l-AP4 into the SNpr reversed reserpine-induced akinesia. Following administration above the SNpc, l-AP4 provided neurochemical, histological and functional protection against 6-OHDA lesion of the nigrostriatal tract. Pretreatment with CPPG inhibited these effects.Conclusions and Implications: These findings highlight group III mGlu receptors in the SN as potential targets for providing both symptomatic and neuroprotective relief in PD, and indicate that inhibition of glutamate release in the SN may underlie these effects. [ABSTRACT FROM AUTHOR]

Background and Purpose: The present study evaluated the role of CB(2) receptors in the regulation of depressive-like behaviours. Transgenic mice overexpressing the CB(2) receptor (CB2xP) were challenged with different types of acute and chronic experimental paradigms to evaluate their response in terms of depressive-like behaviours.Experimental Approach: Tail suspension test (TST), novelty-suppressed feeding test (NSFT) and unpredictable chronic mild stress tests (CMS) were carried out in CB2xP mice. Furthermore, acute and chronic antidepressant-like effects of the CB(2) receptor-antagonist AM630 were evaluated by means of the forced swimming test (FST) and CMS, respectively, in wild-type (WT) and CB2xP mice. CB(2) gene expression, brain-derived neurotrophic factor (BDNF) gene and protein expressions were studied in mice exposed to CMS by real-time PCR and immunohistochemistry, respectively.Key Results: Overexpression of CB(2) receptors resulted in decreased depressive-like behaviours in the TST and NSFT. CMS failed to alter the TST and sucrose consumption in CB2xP mice. In addition, no changes in BDNF gene and protein expression were observed in stressed CB2xP mice. Interestingly, acute administration of AM630 (1 and 3 mg x kg(-1), i.p.) exerted antidepressant-like effects on the FST in WT, but not in CB2xP mice. Chronic administration of AM630 for 4 weeks (1 mg x kg(-1); twice daily, i.p.) blocked the effects of CMS on TST, sucrose intake, CB(2) receptor gene, BDNF gene and protein expression in WT mice.Conclusion and Implications: Taken together, these results suggest that increased CB(2) receptor expression significantly reduced depressive-related behaviours and that the CB(2) receptor could be a new potential therapeutic target for depressive-related disorders. [ABSTRACT FROM AUTHOR]

Background and Purpose: AE9C90CB (N- [(1R, 5S, 6R)-3-azabicyclo [3.1.0] hex-6-ylmethyl]-2-hydroxy-N-methyl-2, 2-diphenylacetamide), a novel muscarinic receptor antagonist, was synthesized for the treatment of overactive bladder. Here we describe the in vitro and in vivo profiles of AE9C90CB for action in bladder over salivary gland and compare it with four agents already in clinical use (tolterodine, oxybutynin, solifenacin and darifenacin).Experimental Approach: Radioligand binding assay and isolated tissue-based functional assay were used to evaluate affinity, potency, and receptor subtype selectivity of compounds. Inhibition of carbachol-induced increase in intravesicular pressure and salivary secretion were measured in anaesthetized rabbits to assess the functional selectivity.Key Results: In vitro radioligand binding study using human recombinant muscarinic receptors showed that AE9C90CB had greater affinity for M(3) muscarinic receptors with pKi of 9.90 +/- 0.11 and was 20-fold more selective for M(3) than for M(2) muscarinic receptors. AE9C90CB exhibited an unsurmountable antagonism on rat bladder strips (pK(B), 9.13 +/- 0.12). In anaesthetized rabbits after intravenous administration, AE9C90CB dose dependently inhibited carbachol-induced increase in intravesicular pressure and salivary secretion, and exhibited functional selectivity for urinary bladder over salivary gland which was ninefold better than that of oxybutynin.Conclusions and Implications: We have identified AE9C90CB, a compound exhibiting moderate selectivity for M(3) over M(2) receptors but greater selectivity for urinary bladder over salivary gland than oxybutynin, tolterodine, solifenacin and darifenacin. Therefore, AE9C90CB may be a promising compound for the treatment of overactive bladder with reduced potential to cause dry mouth than currently available antimuscarinic drugs. [ABSTRACT FROM AUTHOR]

Background and Purpose: The major drug-metabolizing enzymes for the oxidation of oxycodone are CYP2D6 and CYP3A. A high interindividual variability in the activity of these enzymes because of genetic polymorphisms and/or drug-drug interactions is well established. The possible role of an active metabolite in the pharmacodynamics of oxycodone has been questioned and the importance of CYP3A-mediated effects on the pharmacokinetics and pharmacodynamics of oxycodone has been poorly explored.Experimental Approach: We conducted a randomized crossover (five arms) double-blind placebo-controlled study in 10 healthy volunteers genotyped for CYP2D6. Oral oxycodone (0.2 mg x kg(-1)) was given alone or after inhibition of CYP2D6 (with quinidine) and/or of CYP3A (with ketoconazole). Experimental pain (cold pressor test, electrical stimulation, thermode), pupil size, psychomotor effects and toxicity were assessed.Key Results: CYP2D6 activity was correlated with oxycodone experimental pain assessment. CYP2D6 ultra-rapid metabolizers experienced increased pharmacodynamic effects, whereas cold pressor test and pupil size were unchanged in CYP2D6 poor metabolizers, relative to extensive metabolizers. CYP2D6 blockade reduced subjective pain threshold (SPT) for oxycodone by 30% and the response was similar to placebo. CYP3A4 blockade had a major effect on all pharmacodynamic assessments and SPT increased by 15%. Oxymorphone C(max) was correlated with SPT assessment (rho(S)= 0.7) and the only independent positive predictor of SPT. Side-effects were observed after CYP3A4 blockade and/or in CYP2D6 ultra-rapid metabolizers.Conclusions and Implications: The modulation of CYP2D6 and CYP3A activities had clear effects on oxycodone pharmacodynamics and these effects were dependent on CYP2D6 genetic polymorphism. [ABSTRACT FROM AUTHOR]

Background and Purpose: The discovery of the pharmacological functions of nitric oxide has led to the development of NO donor compounds as therapeutic agents. A new generation of ruthenium NO donors, cis-[Ru(NO)(bpy)(2)L]X(n), has been developed, and our aim was to show that these complexes are able to lyse Trypanosoma cruzi in vitro and in vivo.Experimental Approach: NO donors were incubated with T. cruzi and their anti-T. cruzi activities evaluated as the percentage of lysed parasites compared to the negative control. In vivo, trypanocidal activity was evaluated by observing the levels of parasitaemia, survival rate and elimination of amastigotes in mouse myocardial tissue. The inhibition of GAPDH was monitored by the biochemical reduction of NAD(+) to NADH.Key Results: The NO donors cis-[Ru(NO)(bpy)(2)L]X(n) presented inhibitory effects on T. cruzi GAPDH (IC(50) ranging from 89 to 153 microM). The crystal structure of the enzyme shows that the inhibitory mechanism is compatible with S-nitrosylation of the active cysteine (cys166) site. Compounds cis-[Ru(NO)(bpy)(2)imN](PF(6))(3) and cis-[Ru(NO)(bpy)(2)SO(3)]PF(6), at a dose of 385 nmol.kg(-1), yielded survival rates of 80 and 60%, respectively, in infected mice, and eradicated any amastigotes from their myocardial tissue.Conclusions and Implications: The ruthenium compounds exhibited potent in vitro and in vivo trypanocidal activities at doses up to 1000-fold lower than the clinical dose for benznidazole. Furthermore, one mechanism of action of these compounds is via the S-nitrosylation of Cys166 of T. cruzi GAPDH. Thus, these compounds show huge potential as candidates for the development of new drugs for the treatment of Chagas's disease. [ABSTRACT FROM AUTHOR]

Background and Purpose: Some neurosteroids, notably 3alpha-hydroxysteroids, positively modulate GABA(A) receptors, but sulphated steroids negatively modulate these receptors. Recently, other lipophilic amphiphiles have been suggested to positively modulate GABA receptors. We examined whether there was similarity among the actions of these agents and the mechanisms of neurosteroids. Significant similarity would affect theories about the specificity of steroid actions.Experimental Approach: Xenopus laevis oocytes were challenged with Triton X-100, octyl-beta-glucoside, capsaicin, docosahexaenoic acid and sodium dodecyl sulphate (SDS), along with different GABA concentrations.Key Results: These compounds have both positive and negative effects on GABA currents, which can be accentuated according to the degree of receptor activation. A low GABA concentration (1 microM) promoted potentiation and a high concentration (20 microM) promoted inhibition of current, except for SDS that inhibited function even at low GABA concentrations. Amphiphile inhibition was characterized by enhanced apparent desensitization and by weak voltage dependence, similar to pregnenolone sulphate antagonism. We then tested amphiphile effects on mutated receptor subunits that are insensitive to negative (alpha1V256S) and positive (alpha1Q241L or alpha1N407A/Y410F) steroid modulation. Negative regulation by amphiphiles was nearly abolished in alpha1V256S-mutated receptors, but potentiation was unaffected. In alpha1Q241L- or alpha1N407A/Y410F-mutated receptors, potentiation by amphiphiles remained intact.Conclusions and Implications: Structurally diverse amphiphiles have antagonist actions at GABA(A) receptors very similar to those of sulphated neurosteroids, while the potentiating mechanisms of these amphiphiles are distinct from those of neurosteroid-positive modulators. Thus, such antagonism at GABA(A) receptors does not have a clear pharmacophore requirement. [ABSTRACT FROM AUTHOR]

Background and Purpose: Levosimendan is a novel, short half-life calcium sensitizer used as pharmacological inotropic support in acute decompensated heart failure. After oral administration, levosimendan is metabolized to OR-1855, which, in rats, is further metabolized into OR-1896. OR-1896 is a long-lasting metabolite of levosimendan sharing the pharmacological properties of the parent compound.Experimental Approach: Effects of oral OR-1896 treatment on post-infarct heart failure and cardiac remodelling were assessed in diabetic Goto-Kakizaki (GK) rats, an animal model of type II diabetes. Myocardial infarction (MI) was produced to GK rats by coronary ligation. Twenty-four hours after MI or sham operation, the rats were randomized into four groups: (i) MI; (ii) MI + OR-1896 treatment; (iii) sham; and (iv) sham + OR-1896. Cardiac function and markers of cardiac remodelling were assessed 1, 4 and 12 weeks after MI.Key Results: OR-1896 increased ejection fraction and fractional shortening in GK rats with MI. OR-1896 ameliorated post-infarct cardiac hypertrophy, and prevented the MI-induced increase in cardiac mRNA for atrial natriuretic peptide, monocyte chemoattractant protein-1 and connective tissue growth factor, markers of pressure/volume overload, inflammation and fibrosis respectively. OR-1896 also suppressed mRNA for senescence-associated p16(INK4A) and p19(ARF). The beneficial effects of OR-1896 were more prominent at week 12 than at week 4. OR-1896 did not influence systolic blood pressure, blood glucose level, myocardial infarct size or cardiovascular mortality.Conclusions and Implications: Oral treatment with calcium sensitizer OR-1896 protects against post-infarct heart failure and cardiac remodelling in experimental model of type II diabetes. [ABSTRACT FROM AUTHOR]

Background and Purpose: Limited data on the brain penetration of potential stroke treatments have been cited as a major weakness contributing to numerous failed clinical trials. Thus, we tested whether interleukin-1 receptor antagonist (IL-1RA), established as a potent inhibitor of brain injury in animals and currently in clinical development, reaches the brain via a clinically relevant administration route, in experimental stroke.Experimental Approach: Male, Sprague-Dawley rats [either naïve or exposed to middle cerebral artery occlusion (MCAo)] were given a single s.c. dose of IL-1RA (100 mg*kg(-1)). The pharmacokinetic profile of IL-1RA was assessed in plasma and CSF up to 24 h post-administration. Brain tissue distribution of administered IL-1RA was assessed using immunohistochemistry. In a separate experiment, the neuroprotective effect of the single s.c. dose of IL-1RA in MCAo was assessed versus a placebo control group.Key Results: A single s.c. dose of IL-1RA reduced damage caused by MCAo by 33%. This dose resulted in sustained, high concentrations in plasma and CSF, penetrated brain tissue exclusively in areas of blood-brain barrier breakdown and co-localized with morphologically viable neurones. CSF concentrations did not reflect massive parenchymal infiltration of IL-1RA in MCAo animals compared to naïve.Conclusions and Implications: These data are the first to show that a potential treatment for stroke, IL-1RA, rapidly reaches salvageable brain tissue via an administration route that is clinically relevant. This allows confidence that IL-1RA, as a candidate for further clinical development, is able to confer its protective actions both peripherally and centrally. [ABSTRACT FROM AUTHOR]

Background and Purpose: The functional characterization of secreted peptides can provide the basis for the development of novel therapeutic agents. Augurin is a recently identified secreted peptide of unknown function expressed in multiple endocrine tissues, and in regions of the brain including the hypothalamus. We therefore investigated the effect of hypothalamic injection of augurin on the hypothalamo-pituitary-adrenal (HPA) axis in male Wistar rats.Experimental Approach: Augurin was given as a single injection into the third cerebral ventricle (i.c.v.) or into the paraventricular nucleus (iPVN) of the hypothalamus. Circulating hormone levels were then measured by radioimmunoassay. The effect of augurin on the release of hypothalamic neuropeptides was investigated ex vivo using hypothalamic explants. The acute effects of iPVN augurin on behaviour were also assessed.Key Results: i.c.v. injection of augurin significantly increased plasma ACTH and corticosterone, compared with vehicle-injected controls, but had no effect on other hypothalamo-pituitary axes hormones. Microinjection of lower doses of augurin into the PVN caused a similar increase in plasma ACTH and corticosterone, without significant alteration in behavioural patterns. Incubation of hypothalamic explants with increasing doses of augurin significantly elevated corticotrophin-releasing factor (CRF) and arginine vasopressin release. In vivo, peripheral injection of a CRF(1/2) receptor antagonist prevented the rise in ACTH and corticosterone caused by i.c.v. augurin injection.Conclusions and Implications: These data suggest that augurin stimulates the release of ACTH via the release of hypothalamic CRF. Pharmacological manipulation of the augurin system may therefore be a novel target for regulation of the HPA axis. [ABSTRACT FROM AUTHOR]

Background and Purpose: Nebivolol, a selective beta(1)-adrenoceptor antagonist mediating rapid vasodilating effects, is used clinically to treat hypertension. Recently, it was reported that nebivolol also acts as an oestrogen receptor (ER) agonist. To investigate the neuroprotective potential of oestrogens, we assessed the oestrogenic effects of nebivolol in several in vitro neuronal models.Experimental Approach: Human neuroepithelioma SK-N-MC cells stably transfected with human ER alpha and beta, and mouse N2A neuroblastoma cells expressing human APP695(SWE)[N2Aswe, stably transfected with the Swedish mutation form of the Alzheimer-associated amyloid precursor protein (APPswe, K670M/N671L)] were incubated with different concentrations of nebivolol and 17beta-oestradiol (E2) for 24-48 h. ER activation was detected in a specific reporter assay, and ER-dependent gene expression was measured by quantitative real-time PCR (qRT PCR). Furthermore, cell survival rates were determined, and oxidative stress was induced by hydrogen peroxide and paraquat. Amyloid beta protein precursor (APP) processing was investigated, and the cleavage fragments sAPPalpha and Abeta were quantified via alpha-, beta- and gamma-secretase activity assays. Alterations of secretase expression levels were determined by qRT PCR.Key Results: Nebivolol induces oestrogen-dependent gene transcription, and protects neuronal cells against oxidative stress even at low and physiological concentrations (10(-8) M). Moreover, nebivolol modulates processing of APP in mouse neuronal N2Aswe cells by increasing alpha-secretase activity, ultimately leading to enhanced release of soluble non-amyloidogenic sAPPalpha.Conclusions and Implications: We showed that nebivolol acts as ER agonist in neuronal cell lines, and suggest oestrogen-like neuroprotective effects mediated by nebivolol. [ABSTRACT FROM AUTHOR]

Background and Purpose: Tetrandrine, a well-known naturally occurring calcium antagonist with anti-inflammatory, antioxidant and anti-fibrogenetic activities, has long been used clinically for treatment of cardiovascular diseases such as hypertension and arrhythmia. However, little is known about the effect of tetrandrine on cardiac hypertrophy. The aims of the present study were to determine whether tetrandrine could attenuate cardiac hypertrophy and to clarify the underlying molecular mechanisms.Experimental Approach: Tetrandrine (50 mg x kg(-1) x day(-1)) was administered by oral gavage three times a day for one week and then the mice were subjected to either chronic pressure overload generated by aortic banding (AB) or sham surgery (control group). Cardiac function was determined by echocardiography.Key Results: Tetrandrine attenuated the cardiac hypertrophy induced by AB, as assessed by heart weight/body weight and lung weight/body weight ratios, cardiac dilatation and the expression of genes of hypertrophic markers. Tetrandrine also inhibited fibrosis and attenuated the inflammatory response. The cardioprotective effects of tetrandrine were mediated by blocking the increased production of reactive oxygen species and the activation of ERK1/2-dependent nuclear factor-kappaB and nuclear factor of activated T cells that occur in response to hypertrophic stimuli.Conclusions and Implications: Taken together, our results suggest that tetrandrine can improve cardiac function and prevent the development of cardiac hypertrophy by suppressing the reactive oxygen species-dependent ERK1/2 signalling pathway. [ABSTRACT FROM AUTHOR]

Background and Purpose: Experimental and clinical data suggest that extracts of Ginkgo biloba improve cognitive function. However, the neurochemical correlates of these effects are not yet fully clarified. The purpose of this study was to examine the effects of acute and repeated oral administration of the standardized extract EGb 761((R)) on extracellular levels of dopamine, noradrenaline and serotonin (5-HT), and the dopamine metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the prefrontal cortex (PFC) and striatum of conscious rats.Experimental Approach: Monoamines and their metabolites were monitored by the use of microdialysis sampling and HPLC with electrochemical or fluorescence detection.Key Results: A single oral dose of EGb 761 (100 mg.kg(-1)) had no effect on monoamine levels. However, following chronic (100 mg.kg(-1)/14 days/once daily) treatment, the same dose significantly increased extracellular dopamine and noradrenaline levels, while 5-HT levels were unaffected. Chronic treatment with EGb 761 showed dose-dependent increases in frontocortical dopamine levels and, to a lesser extent, in the striatum. The extracellular levels of HVA and DOPAC were not affected by either acute or repeated doses. Treatment with the main constituents of EGb 761 revealed that the increase in dopamine levels was mostly caused by the flavonol glycosides and ginkgolide fractions, whereas bilobalide treatment was without effect.Conclusions and Implications: The present results demonstrate that chronic but not acute treatment with EGb 761 increased dopaminergic transmission in the PFC. This finding may be one of the mechanisms underlying the reported effects of G. biloba in improving cognitive function. [ABSTRACT FROM AUTHOR]

Background and Purpose: The current study was designed to: (i) examine whether functional interactions occur between receptors known to regulate alcohol self-administration; and (ii) characterize relapse to alcohol seeking following abstinence.Experimental Approach: The selective cannabinoid CB(1) receptor antagonist SR141716A (0.03-1.0 mg.kg(-1) i.p.) resulted in a dose-dependent reduction in ethanol self-administration in ethanol-preferring Indiana-preferring rats. SR141716A was then co-administered with either the selective glutamate metabotropic glutamate 5 (mGlu(5)) receptor antagonist 3-[(2-methyl-1,3-thiazol-4-yl)ethynyl]pyridine (MTEP) or the selective adenosine A(2A) receptor antagonist SCH58261.Key Results: When administered at individually sub-threshold doses, a combination of SR141716A (0.1 mg.kg(-1)) and SCH58261 (0.5 mg.kg(-1) i.p.) produced a reduction (28%) in ethanol self-administration. Combinations of threshold doses of SR141716A (0.3 mg.kg(-1)) and SCH58261 (2.0 mg.kg(-1), i.p.) caused an essentially additive reduction (68%) in alcohol self-administration. A combination of individually sub-threshold doses of CB(1) and mGlu(5) receptor antagonists did not affect alcohol self-administration; however, combined threshold doses of SR141716A (0.3 mg.kg(-1)) and MTEP (1.0 mg.kg(-1) i.p.) did reduce ethanol self-administration markedly (80%). Cue-conditioned alcohol seeking was attenuated by pretreatment with MTEP (1.0 mg.kg(-1)) co-administered with SR141716A (0.3 mg.kg(-1) i.p.). In contrast, SCH58261 (2.0 mg.kg(-1)) co-administered with SR141716A (0.3 mg.kg(-1) i.p.) did not reduce cue-conditioned alcohol seeking.Conclusions and Implications: Adenosine A(2A) and cannabinoid CB(1) receptors regulated alcohol self-administration additively, but combined low-dose antagonism of these receptors did not prevent cue-conditioned alcohol seeking after abstinence. In contrast, combined low-dose antagonism of mGlu(5) and CB(1) receptors did prevent relapse-like alcohol seeking after abstinence, suggesting a prominent role for mGlu(5) receptors in this paradigm. [ABSTRACT FROM AUTHOR]

Background and Purpose: The intracellular pH (pHi) of neurones is tightly regulated by, for example, membrane-bound acid-exchangers and loaders. Nevertheless, excessive bioelectric activity lowers steady-state pHi. In turn, even a moderate acidification can inhibit neuronal activity, a process believed to be part of a negative feedback loop controlling neuronal excitation. As moclobemide, an antidepressant, and also some antiepileptic drugs can reduce neuronal pHi in hippocampus slices in vitro, we screened a panel of currently used neuropsychopharmaca for comparable effects.Experimental Approach: BCECF-AM loaded hippocampal slices were superfused with 16 different neuroleptics, antidepressants and antiepileptics under bicarbonate-buffered conditions. Changes in steady-state pHi of CA3 neurones were measured fluorometrically.Key Results: The antipsychotics haloperidol, clozapine, ziprasidone, and the antidepressants amitriptyline, doxepin, trimipramine, citalopram, mirtazapine, as well as the anticonvulsive drug tiagabine reversibly reduced the steady-state pHi by up to 0.35 pH-units in concentrations of 5-50 microM. In contrast, venlafaxine, the anticonvulsants carbamazepine, clonazepam, gabapentin, lamotrigine, zonisamide, and the mood stabilizer lithium had no effect on neuronal pHi.Conclusion and Implications: These data substantiate the view that clinically relevant concentrations of neuroleptics and antidepressants can mediate changes in neuronal pHi, which may contribute to their pharmacological mode of action. Effects on pHi should be taken into account when therapeutic or even harmful effects of these drugs are evaluated. [ABSTRACT FROM AUTHOR]

Background and Purpose: Certain saponins synergize with antitumour drugs to enhance their efficacy, but the mechanisms underlying this synergy in vivo are not well studied. Here, we describe the distribution of Saponinum album (Spn) from Gypsophila paniculata L. in mice after subcutaneous injection.Experimental Approach: The [(3)H]-labelled Spn used for in vivo experiments was biologically active, as it still increased the cytotoxicity of a chimeric toxin in vitro. Distribution of [(3)H]-Spn was measured in BALB/c mice, with or without subcutaneous tumours in the flank. Labelled Spn was subcutaneously injected in the neck, and samples of organs, blood, urine and tumour tissue were analysed for radioactivity, 5-240 min after the injection.Key Results: The majority of [(3)H]-Spn distributed within 10 min throughout the entire animal, with high levels of radioactivity in the urine by 30 min. No preferential accumulation in tumour tissue or other organs was observed. In tumour-bearing mice, using a sequential combination of Spn (given first) and a chimeric toxin against the epidermal growth factor receptor, ErbB1, we tested two different pretreatment times for Spn. There was high antitumour efficacy (66% inhibition of tumour growth) after 60 min pre treatment with Spn, but no significant inhibition after 10 min pre treatment with Spn.Conclusions and Implications: [(3)H]-Spn was rapidly cleared from the mice after s.c. injection, and antitumour synergy with chimeric toxins was correlated with the removal of excess Spn from tissues. Disposition of Spn in vivo may critically determine antitumour synergy with chimeric toxins. [ABSTRACT FROM AUTHOR]

Background and Purpose: The effects of statins on diabetes mellitus (DM) are controversial, and their effects on pancreatic fibrosis are poorly defined. We investigated the effect of long- and short-term treatments with pravastatin on the development of DM and pancreatic fibrosis in DM-prone Otsuka-Long-Evans-Tokushima Fatty (OLETF) rats.Experimental Approach: Male OLETF rats were divided into four groups at 12 weeks of age. The first group received a standard rat diet until the end of the experimental period at age 80 weeks. The second group was given a diet containing 0.05% pravastatin from 12 weeks of age, before the onset of DM and pancreatic fibrosis, and the third group was given the same pravastatin diet from 28 weeks of age, after the onset of DM and pancreatic fibrosis, until age 80 weeks. The fourth group received the same pravastatin diet only for 16 weeks, from 12 to 28 weeks of age, and switched to a standard diet. Progressions of DM and pancreatic fibrosis were evaluated.Key Results: Long-term treatments with pravastatin, either from 12 or 28 weeks of age, decreased serum glucose concentration and fibrotic area, elevated superoxide dismutase activity and down-regulated transforming growth factor-beta1 mRNA in the pancreas. In contrast, after a short-term treatment with pravastatin, these parameters markedly deteriorated after its cessation.Conclusions and Implications: The results suggest that long-term treatment with pravastatin improves DM and pancreatic fibrosis via anti-oxidative and anti-fibrotic properties, whereas cessation of pravastatin abolishes these beneficial effects, and accelerates DM and pancreatic fibrosis. [ABSTRACT FROM AUTHOR]

Background and Purpose: Blebbistatin, an inhibitor of myosin-II-specific ATPase, has been used to inhibit contraction of invertebrate and mammalian muscle preparations containing non-muscle myosin. Activated hepatic stellate cells have contractile properties and play an important role in the pathophysiology of liver fibrosis and portal hypertension. Therefore, hepatic stellate cells are considered as therapeutic target cells. In the present study, we studied the effect of blebbistatin during the transition of mouse hepatic stellate cells into contractile myofibroblasts.Experimental Approach: Effects of blebbistatin on cell morphology were evaluated by phase contrast microscopy. Cell stress fibres and focal adhesions were investigated by dual immunofluorescence staining and visualized using fluorescence microscopy. Contractile force generation was examined by silicone wrinkle formation assays and collagen gel contraction assays. Intracellular Ca(2+) release in response to endothelin-1 was measured by using Fluo-4. Cell migration was measured by wound healing experiments.Key Results: In culture-activated hepatic stellate cells, blebbistatin was found to change both cell morphology and function. In the presence of blebbistatin, stellate cells became smaller, acquired a dendritic morphology and had less myosin IIA-containing stress fibres and vinculin-containing focal adhesions. Moreover, blebbistatin impaired silicone wrinkle formation, reduced collagen gel contraction and blocked endothelin-1-induced intracellular Ca(2+) release. Finally, it promoted wound-induced cell migration.Conclusions and Implications: By inhibiting myosin II ATPase, blebbistatin has profound effects on the morphology and function of activated hepatic stellate cells. Our data suggest that myosin II could be a therapeutic target in the treatment of liver fibrosis and portal hypertension. [ABSTRACT FROM AUTHOR]

Background and Purpose: ABC multidrug transporters (MDR-ABC proteins) cause multiple drug resistance in cancer and may be involved in the decreased anti-cancer efficiency and modified pharmacological properties of novel specifically targeted agents. It has been documented that ABCB1 and ABCG2 interact with several first-generation, small-molecule, tyrosine kinase inhibitors (TKIs), including the Bcr-Abl fusion kinase inhibitor imatinib, used for the treatment of chronic myeloid leukaemia. Here, we have investigated the specific interaction of these transporters with nilotinib, dasatinib and bosutinib, three clinically used, second-generation inhibitors of the Bcr-Abl tyrosine kinase activity.Experimental Approach: MDR-ABC transporter function was screened in both membrane- and cell-based (K562 cells) systems. Cytotoxicity measurements in Bcr-Abl-positive model cells were coupled with direct determination of intracellular TKI concentrations by high-pressure liquid chromatography-mass spectrometry and analysis of the pattern of Bcr-Abl phosphorylation. Transporter function in membranes was assessed by ATPase activity.Key Results: Nilotinib and dasatinib were high-affinity substrates of ABCG2, and this protein mediated an effective resistance in cancer cells against these compounds. Nilotinib and dasatinib also interacted with ABCB1, but this transporter provided resistance only against dasatinib. Neither ABCB1 nor ABCG2 induced resistance to bosutinib. At relatively higher concentrations, however, each TKI inhibited both transporters.Conclusions and Implications: A combination of in vitro assays may provide valuable preclinical information for the applicability of novel targeted anti-cancer TKIs, even in multidrug-resistant cancer. The pattern of MDR-ABC transporter-TKI interactions may also help to understand the general pharmacokinetics and toxicities of new TKIs. [ABSTRACT FROM AUTHOR]

Background and Purpose: The lipid phosphatase known as SH2 domain-containing inositol 5'-phosphatase 2 (SHIP2) plays an important role in the regulation of the intracellular insulin signalling pathway. Recent studies have suggested that inhibition of SHIP2 could produce significant benefits in treatment of type 2 diabetes. However, there were no small molecule SHIP2 inhibitors and we, therefore, aimed to identify this type of compound.Experimental Approach: The phosphatase assay with malachite green was used for high-throughput screening. The pharmacological profiles of suitable compounds were further characterized in phosphatase assays, cellular assays and oral administration in normal and diabetic (db/db) mice.Key Results: During high-throughput screening, AS1949490 was identified as a potent SHIP2 inhibitor (IC(50)= 0.62 microM for SHIP2). This compound was also selective for SHIP2 relative to other intracellular phosphatases. In L6 myotubes, AS1949490 increased the phosphorylation of Akt, glucose consumption and glucose uptake. In FAO hepatocytes, AS1949490 suppressed gluconeogenesis. Acute administration of AS1949490 inhibited the expression of gluconeogenic genes in the livers of normal mice. Chronic treatment of diabetic db/db mice with AS1949490 significantly lowered the plasma glucose level and improved glucose intolerance. These in vivo effects were based in part on the activation of intracellular insulin signalling pathways in the liver.Conclusions and Implications: This is the first report of a small molecule inhibitor of SHIP2. This compound will help to elucidate the physiological functions of SHIP2 and its involvement in various diseases, such as type 2 diabetes. [ABSTRACT FROM AUTHOR]

Chemical signalling is the main mechanism by which biological function is controlled at all levels, from the single cell to the whole organism. Chemical recognition is the function of receptors, which, in addition to recognising endogenous chemical signals, are also the target of many important experimental and therapeutic drugs. Receptors, therefore, lie at the heart of pharmacology. This article describes the way in which the receptor concept originated early in the 20th century, and evolved through a highly innovative stage of quantitative theory based on chemical kinetics, to the point where receptors were first isolated and later cloned, until we now have a virtually complete catalogue of all the receptors present in the genome. Studies on signal transduction are revealing great complexity in the events linking ligand binding to the physiological or therapeutic response. Though some simple quantitative rules of ‘receptor theory’ are still useful, the current emphasis is on unravelling the pathways that link receptors to responses, and it will be some time before we know enough about them to embark on the next phase of ‘receptor theory’.British Journal of Pharmacology (2006) 147, S9–S16. doi:10.1038/sj.bjp.0706457 [ABSTRACT FROM AUTHOR]

Background and Purpose: 2‐Hydroxypropyl‐β‐cyclodextrin (HPCD) is an FDA approved vehicle for drug delivery and an efficient cholesterol‐lowering agent. HPCD was proposed to lower tissue cholesterol via multiple mechanisms including those mediated by oxysterols. CYP27A1 and CYP46A1 are the major oxysterol‐producing enzymes in the retina that convert cholesterol to 27‐ and 24‐hydroxycholesterol, respectively. We investigated whether HPCD treatments affected the retina of wild‐type and Cyp27a1−/−Cyp46a1−/− mice that do not produce the major retinal oxysterols. Experimental Approach HPCD administration was either by i.p., p.o. or s.c. Delivery to the retina was confirmed by angiography using the fluorescently labelled HPCD. Effects on the levels of retinal sterols, mRNA and proteins were evaluated by GC–MS, qRT‐PCR and label‐free approach, respectively. Key Results: In both wild‐type and Cyp27a1−/−Cyp46a1−/− mice, HPCD crossed the blood–retinal barrier when delivered i.p. and lowered the retinal cholesterol content when administered p.o. and s.c. In both genotypes, oral HPCD treatment affected the expression of cholesterol‐related genes as well as the proteins involved in endocytosis, lysosomal function and lipid homeostasis. Mechanistically, liver X receptors and the altered expression of Lipe (hormone‐sensitive lipase), Nceh1 (neutral cholesterol ester hydrolase 1) and NLTP (non‐specific lipid‐transfer protein) could mediate some of the HPCD effects. Conclusions and Implications: HPCD treatment altered retinal cholesterol homeostasis and is a potential therapeutic approach for the reduction of drusen and subretinal drusenoid deposits, cholesterol‐rich lesions and hallmarks of age‐related macular degeneration. LINKED ARTICLES: This article is part of a themed issue on Oxysterols, Lifelong Health and Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.16/issuetoc [ABSTRACT FROM AUTHOR]

Background and Purpose: Niemann-Pick disease type C (NPC) is a lysosomal storage disorder with disrupted intracellular cholesterol trafficking. A cyclic heptasaccharide, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), is a cholesterol solubilizer that is being developed to treat NPC, but its ototoxicity and pulmonary toxicity remain important issues. We have characterized 2-hydroxypropyl-γ-cyclodextrin (HP-γ-CD), a cyclic octasaccharide with a larger cavity than HP-β-CD, as a candidate drug to treat NPC. However, the molecular target of HP-γ-CD with respect to NPC and its potential for clinical application are still unclear.Experimental Approach: We investigated the mode of interaction between HP-γ-CD and cholesterol by phase-solubility analysis, proton NMR spectroscopy and molecular dynamics simulations. We then evaluated the therapeutic effects of HP-γ-CD compared with HP-β-CD using cellular and murine NPC models. Mouse auditory and pulmonary function tests were also conducted.Key Results: HP-γ-CD solely formed a 1:1 inclusion complex with cholesterol with an affinity similar to that of HP-β-CD. In vitro, HP-γ-CD and HP-β-CD amelioration of NPC-related manifestations was almost equivalent at lower concentrations. However, at higher concentrations, the cholesterol inclusion mode of HP-β-CD shifted to the highly soluble 2:1 complex whereas that of HP-γ-CD maintained solely the 1:1 complex. The constant lower cholesterol solubilizing ability of HP-γ-CD conferred it with significantly reduced toxicity compared with HP-β-CD, but equal efficacy in treating a mouse model of NPC.Conclusions and Implications: HP-γ-CD can serve as a fine-tuned cholesterol solubilizer for the treatment of NPC with a wider safety margin than HP-β-CD in terms of ototoxicity and pulmonary toxicity. [ABSTRACT FROM AUTHOR]

Exosomes are a subset of extracellular vesicles essential for cell-cell communication in health and disease with the ability to transport nucleic acids, functional proteins and other metabolites. Their clinical use as diagnostic biomarkers and therapeutic carriers has become a major field of research over recent years, generating rapidly expanding scientific interest and financial investment. Their reduced immunogenicity compared to liposomes or viral vectors and their ability to cross major physiological barriers like the blood-brain barrier make them an appealing and innovative option as biomarkers and therapeutic agents. Here, we review the latest clinical developments of exosome biotechnology for diagnostic and therapeutic purposes, including the most recent COVID-19-related exosome-based clinical trials. We present current exosome engineering strategies for optimal clinical safety and efficacy, and assess the technology developed for good manufacturing practice compliant scaling up and storage approaches along with their limitations in pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Advances in the design of potential bone-selective drugs for the treatment of various bone-related diseases are creating exciting new directions for multiple unmet medical needs. For bone-related cancers, off-target/non-bone toxicities with current drugs represent a significant barrier to the quality of life of affected patients. For bone infections and osteomyelitis, bacterial biofilms on infected bones limit the efficacy of antibiotics because it is hard to access the bacteria with current approaches. Promising new experimental approaches to therapy, based on bone-targeting of drugs, have been used in animal models of these conditions and demonstrate improved efficacy and safety. The success of these drug-design strategies bodes well for the development of therapies with improved efficacy for the treatment of diseases affecting the skeleton. LINKED ARTICLES: This article is part of a themed issue on The molecular pharmacology of bone and cancer-related bone diseases. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.9/issuetoc. [ABSTRACT FROM AUTHOR]

Background and Purpose: The protein V‐domain immunoglobulin suppressor of T‐cell activation (VISTA) is a novel immune‐checkpoint molecule that belongs to the B7 family and regulates a broad spectrum of immune responses. So far, low MW compounds targeting VISTA for the treatment of autoimmune diseases or inflammation, have not been identified. Experimental Approach We developed a homology modelling for VISTA 3D structure and subsequent virtual screening for low MW ligands binding to VISTA. Visualization of the binding postures of docked ligands with protein VISTA indicated that compound M351‐0056 targeted VISTA. The biological activities of compound M351‐0056 targeting VISTA were investigated in vitro using monocytes and T cells and in vivo, using mice with imiquimod‐induced dermatitis. Key Results: The KD value of M351‐0056 for human VISTA‐extracellular domain was 12.60 ± 3.84 μM as assessed by microscale thermophoresis. M351‐0056 decreased cytokine secretion from PBMCs or human CD4+ T cells, suppressed proliferation of PBMCs and enhanced expression of Foxp3+ T cells. These effects of M351‐0056 modulating VISTA involved the JAK2–STAT2 pathway. Daily administration of M351‐0056 ameliorated imiquimod‐induced psoriasis‐like dermatitis. Expression of mRNA and protein of inflammatory cytokines in psoriatic lesions was decreased after M351‐0056 treatment. Conclusion and Implications: The compound M351‐0056 showed high affinity for VISTA and may modulate its immune function in vitro and in vivo. Our finding provides a lead compound for therapeutically enhancing VISTA‐mediated pathways to benefit the treatment of autoimmune diseases or inflammation. [ABSTRACT FROM AUTHOR]

Background and Purpose: Miltefosine is an alkylphosphocholine drug with proven effectiveness against various types of parasites and cancer cells. Miltefosine is not only able to induce direct parasite killing but also modulates host immunity, for example by reducing the severity of allergies in patients. To date, there are no reports on the effect of miltefosine on eosinophils, central effector cells involved in allergic inflammation. Experimental Approach We tested the effect of miltefosine on the activation of human eosinophils and their effector responses in vitro and in mouse models of eosinophilic migration and ovalbumin‐induced allergic lung inflammation. Key Results: The addition of miltefosine suppressed several eosinophilic effector reactions such as CD11b up‐regulation, degranulation, chemotaxis and downstream signalling. Miltefosine significantly reduced the infiltration of immune cells into the respiratory tract of mice in an allergic cell recruitment model. Finally, in a model of allergic inflammation, treatment with miltefosine resulted in an improvement of lung function parameters. Conclusion and Implications: Our observations suggest a strong modulatory activity of miltefosine in the regulation of eosinophilic inflammation in vitro and in vivo. Our data underline the potential efficacy of miltefosine in the treatment of allergic diseases and other eosinophil‐associated disorders and may raise important questions regarding the immunomodulatory effect of miltefosine in patients treated for leishmania infections. [ABSTRACT FROM AUTHOR]

Intense efforts are underway to evaluate potential therapeutic agents for the treatment of COVID-19. In order to respond quickly to the crisis, the repurposing of existing drugs is the primary pharmacological strategy. Despite the urgent clinical need for these therapies, it is imperative to consider potential safety issues. This is important due to the harm-benefit ratios that may be encountered when treating COVID-19, which can depend on the stage of the disease, when therapy is administered and underlying clinical factors in individual patients. Treatments are currently being trialled for a range of scenarios from prophylaxis (where benefit must greatly exceed risk) to severe life-threatening disease (where a degree of potential risk may be tolerated if it is exceeded by the potential benefit). In this perspective, we have reviewed some of the most widely researched repurposed agents in order to identify potential safety considerations using existing information in the context of COVID-19. [ABSTRACT FROM AUTHOR]

Metastatic bone disease is a serious clinical complication for the treatment of patients with advanced cancer, but few therapeutic options are currently available. Bisphosphonates are an established standard care for these patients, but new treatments are now emerging, including the use of monoclonal antibodies targeting the RANK ligand. In this issue of the BJP, Reuter et al. provide evidence that thiocolchicoside, a semi-synthetic derivative of the naturally occurring colchicoside, extracted from the seeds of Gloriosa superba (Liliaceae), prevented osteoclactogenesis by suppressing RANK ligand-mediated NF-κB activation. Thiolcolchicoside may thus represent an attractive therapeutic option for the management of bone metastatic disease. LINKED ARTICLE This article is a commentary on Reuter et al., pp. 2127-2139 of this issue. To view this paper visit [ABSTRACT FROM AUTHOR]

This article summarizes the findings of Kameda et al. (this issue of BJP) that suggest a new avenue for the pharmacological treatment of subarachnoid haemorrhage (SAH) involving the combined use of a proteinase inhibitor (argatroban) that targets thrombin and an antioxidant (vitamin C). The findings are presented in the context of previous modalities of treating SAH that are of modest impact and the possibility that inhibiting proteinase-mediated signalling via proteinase-activated receptors like the thrombin PAR1 receptor combined with blocking oxidative stress may provide a new avenue for the treatment of SAH. LINKED ARTICLE This article is a commentary on Kameda et al., pp. 106-119 of this issue. To view this paper visit [ABSTRACT FROM AUTHOR]

Background and Purpose: Immunosuppressive drugs have shown great promise in treating autoimmune diseases in recent years. A series of novel oxazole derivatives were screened for their immunosuppressive activity. PO-322 [1H-indole-2,3-dione 3-(1,3-benzoxazol-2-ylhydrazone)] was identified as the most effective of these compounds. Here, we have investigated the mechanism(s) underlying the inhibition of T-cell proliferation in vitro by PO-322, as well as its effects on the delayed-type hypersensitivity (DTH) response and imiquimod-induced dermatitis in vivo.Experimental Approach: T-cell proliferation and apoptosis were analysed with flow cytometry. Cell viability was assessed with a CCK-8 assay. Protein kinase activity was assessed by SelectScreen Kinase Profiling Services. The phosphorylation of signal-regulated molecules was measured by Western blot. Cytokine levels were determined by elisa. The effect of PO-322 on DTH and imiquimod-induced dermatitis was evaluated in BALB/c mice.Key Results: PO-322 inhibited human T-cell proliferation with anti-CD3/anti-CD28 mAbs or alloantigen without significant cytotoxicity. Importantly, PO-322 was a selective inhibitor of the serum- and glucocorticoid-regulated kinase 1 (SGK1) and decreased NDRG1 phosphorylation but not p70S6K, STAT5, Akt, or ERK1/2 phosphorylation. Furthermore, PO-322 inhibited IFN-γ, IL-6, and IL-17 expression but not IL-10 expression. Finally, treatment with PO-322 was safe and effective for ameliorating the DTH response and imiquimod-induced dermatitis in mice.Conclusions and Implications: PO-322 exerted immunosuppressive activity in vitro and in vivo by selectively inhibiting SGK1 activity. PO-322 represents a potential lead compound for the design and development of new drugs for the treatment of autoimmune diseases. [ABSTRACT FROM AUTHOR]

Background and Purpose: Inhibition of the T- and B-cell interaction through the CD40/CD40 ligand (L) axis is a favourable approach for inflammatory disease treatment. Clinical studies of anti-CD40L molecules in autoimmune diseases have met challenges because of thromboembolic events and adverse haemostasis. VIB4920 (formerly MEDI4920) is a novel CD40L antagonist and Tn3 fusion protein designed to prevent adverse haemostasis and immunopharmacology. We evaluated the pharmacokinetics, activity and toxicity of VIB4920 in monkeys.Experimental Approach: Cynomolgus monkeys received i.v. or s.c. 5-300 mg·kg-1 VIB4920 or vehicle, once weekly for 1 month (Studies 1 and 2) or 28 weeks (Study 3). VIB4920 exposure and bioavailability were determined using pharmacokinetic analyses, and immune cell population changes via flow cytometry. Pharmacological activity was evaluated by measuring the animals' capacity to elicit an immune response to keyhole limpet haemocyanin (KLH) and tetanus toxoid (TT).Key Results: VIB4920 demonstrated linear pharmacokinetics at multiple doses. Lymphocyte, monocyte, cytotoxic T-cell and NK cell counts were not significantly different between treatment groups. B-cell counts reduced dose-dependently and the T-cell dependent antibody response to KLH was suppressed by VIB4920 dose-dependently. The recall response to TT was similar across treatment groups. No thromboembolic events or symptoms of immune system dysfunctionality were observed.Conclusions and Implications: VIB4920 demonstrated an acceptable safety profile in monkeys. VIB4920 showed favourable pharmacokinetics, dose-dependent inhibition of a neoantigen-specific immune response and no adverse effects on immune function following long-term use. Our data support the use of VIB4920 in clinical trials. [ABSTRACT FROM AUTHOR]

Background and Purpose: Diacetyl-bis(4-methyl-3-thiosemicarbazonato)copperII (CuII (atsm)) ameliorates neurodegeneration and delays disease progression in mouse models of amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD), yet the mechanism of action remains uncertain. Promising results were recently reported for separate Phase 1 studies in ALS patients and PD patients. Affected tissue in these disorders shares features of elevated Fe, low glutathione and increased lipid peroxidation consistent with ferroptosis, a novel form of regulated cell death. We therefore evaluated the ability of CuII (atsm) to inhibit ferroptosis.Experimental Approach: Ferroptosis was induced in neuronal cell models by inhibition of glutathione peroxidase-4 activity with RSL3 or by blocking cystine uptake with erastin. Cell viability and lipid peroxidation were assessed and the efficacy of CuII (atsm) was compared to the known antiferroptotic compound liproxstatin-1.Key Results: CuII (atsm) protected against lipid peroxidation and ferroptotic lethality in primary and immortalised neuronal cell models (EC50 : ≈130 nM, within an order of magnitude of liproxstatin-1). NiII (atsm) also prevented ferroptosis with similar potency, whereas ionic CuII did not. In cell-free systems, CuII (atsm) and NiII (atsm) inhibited FeII -induced lipid peroxidation, consistent with these compounds quenching lipid radicals.Conclusions and Implications: The antiferroptotic activity of CuII (atsm) could therefore be the disease-modifying mechanism being tested in ALS and PD trials. With potency in vitro approaching that of liproxstatin-1, CuII (atsm) possesses favourable properties such as oral bioavailability and entry into the brain that make it an attractive investigational product for clinical trials of ferroptosis-related diseases. [ABSTRACT FROM AUTHOR]

Background and Purpose: Atherosclerosis is a chronic inflammatory disease, and retinoid X receptor-α (RXRα) is an intriguing anti-atherosclerosis target. This study investigated whether and how an RXRα modulator, K-80003, derived from a non-steroidal anti-inflammatory drug attenuates atherosclerotic plaque progression and destabilization.Experimental Approach: Our previously established ApoE-/- mouse model of carotid vulnerable plaque progression was treated with K-80003 or vehicle for 4 or 8 weeks. Samples of carotid arteries and serum were collected to determine atherosclerotic lesion size, histological features, expression of related proteins, and lipid profiles. In vitro studies were carried out in 7-ketocholesterol (7-KC)-stimulated macrophages treated with or without K-80003.Key Results: K-80003 significantly reduced lesion size, plaque rupture, macrophage infiltration, and inflammatory cytokine levels. Plaque macrophages positive for nuclear p65 (RelA) NF-κB subunit were markedly reduced after K-80003 treatment. Also, K-80003 treatment inhibited 7-KC-induced p65 nuclear translocation, IκBα degradation, and transcription of NF-κB target genes. In addition, K-80003 inhibited NF-κB pathway mainly through the reduction of p62/sequestosome 1 (SQSTM1), probably due to promotion of autophagic flux by K-80003. Mechanistically, cytoplasmic localization of RXRα was associated with decreased autophagic flux. Increasing cytoplasmic RXRα expression by overexpression of RXRα/385 mutant decreased autophagic flux in RAW264.7 cells. Finally, K-80003 strongly inhibited 7-KC-induced RXRα cytoplasmic translocation.Conclusions and Implications: K-80003 suppressed atherosclerotic plaque progression and destabilization by promoting macrophage autophagic flux and consequently inhibited the p62/SQSTM1-mediated NF-κB proinflammatory pathway. Thus, targeting RXRα-mediated autophagy-inflammation axis by its noncanonical modulator may represent a promising strategy to treat atherosclerosis. [ABSTRACT FROM AUTHOR]

The α1A -adrenoceptor is abundantly expressed in the lower urinary tract and is the principal therapeutic target for the symptomatic treatment of lower urinary tract symptoms in men. Prazosin has a lower affinity for the lower urinary tract α1A -adrenoceptor than α1A -adrenoceptors found in other parts of the body. This has led to the lower urinary tract α1A -adrenoceptor being subclassified as an α1L -adrenoceptor. It was demonstrated that this pharmacologically distinct α1L -adrenoceptor is a product of the α1A -adrenoceptor gene, but the mechanism by which this altered phenotype is achieved remains a mystery. Hypotheses for this altered pharmacology include the presence of an interacting protein such as cysteine-rich with EGF-like domain (CRELD) 1 or other GPCRs such as the CXCR2 chemokine or 5-HT1B receptor. Alternatively, the influence of breast cancer resistance protein (BCRP) efflux transporters on the pharmacology of α1A -adrenoceptors has also been investigated. These and other hypotheses will be described and discussed in this review. LINKED ARTICLES: This article is part of a themed section on Adrenoceptors-New Roles for Old Players. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.14/issuetoc. [ABSTRACT FROM AUTHOR]

Arterial hypertension represents a serious public health problem, being a major cause of morbidity and mortality worldwide. The availability of many antihypertensive therapeutic strategies still fails to adequately treat around 20% of hypertensive patients, who are considered resistant to conventional treatment. In the pathogenesis of hypertension, immune system mechanisms are activated and both the innate and adaptive immune responses play a crucial role. However, what, when and how the immune system is triggered during hypertension development is still largely undefined. In this context, this review highlights scientific advances in the manipulation of the immune system in order to attenuate hypertension and end-organ damage. Here, we discuss the potential use of immunosuppressants and immunomodulators as pharmacological tools to control the activation of the immune system, by non-specific and specific mechanisms, to treat hypertension and improve end-organ damage. Nevertheless, more clinical trials should be performed with these drugs to establish their therapeutic efficacy, safety and risk-benefit ratio in hypertensive conditions. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc. [ABSTRACT FROM AUTHOR]

A conference paper about the effect of the withdrawal of endogenous estrogen by ovariectomy and the replacement by chronic administration of 17β-estradiol on ischemia-induced arrhythmias is presented. It discusses that female Wistar rats are ovariectomized under Hypnorm/diazepam anesthesia. Results show that chronic administration of 17β-estradiol does not significantly reduce ischemia-induced arrhythmias.

Background and Purpose: Numerous claims are made for cannabis' therapeutic utility upon human seizures, but concerns persist about risks. A potential confounder is the presence of both Δ9 -tetrahydrocannabinol (THC), variously reported to be pro- and anticonvulsant, and cannabidiol (CBD), widely confirmed as anticonvulsant. Therefore, we investigated effects of prolonged exposure to different THC/CBD cannabis extracts on seizure activity and associated measures of endocannabinoid (eCB) system signalling.Experimental Approach: Cannabis extract effects on in vivo neurological and behavioural responses, and on bioanalyte levels, were measured in rats and dogs. Extract effects on seizure activity were measured using electroencephalography telemetry in rats. eCB signalling was also investigated using radioligand binding in cannabis extract-treated rats and treatment-naïve rat, mouse, chicken, dog and human tissue.Key Results: Prolonged exposure to cannabis extracts caused spontaneous, generalized seizures, subserved by epileptiform discharges in rats, but not dogs, and produced higher THC, but lower 11-hydroxy-THC (11-OH-THC) and CBD, plasma concentrations in rats versus dogs. In the same rats, prolonged exposure to cannabis also impaired cannabinoid type 1 receptor (CB1 receptor)-mediated signalling. Profiling CB1 receptor expression, basal activity, extent of activation and sensitivity to THC suggested interspecies differences in eCB signalling, being more pronounced in a species that exhibited cannabis extract-induced seizures (rat) than one that did not (dog).Conclusions and Implications: Sustained cannabis extract treatment caused differential seizure, behavioural and bioanalyte levels between rats and dogs. Supporting radioligand binding data suggest species differences in eCB signalling. Interspecies variations may have important implications for predicting cannabis-induced convulsions from animal models.Linked Articles: This article is part of a themed section on 8th European Workshop on Cannabinoid Research. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.10/issuetoc. [ABSTRACT FROM AUTHOR]

Background and Purpose: Endocannabinoids and related N-acylethanolamines (NAEs) are involved in regulation of gut function, but relatively little is known as to whether inflammatory cytokines such as IFNγ affect their levels. We have investigated this in vitro using cultures of T84 colon cancer cells.Experimental Approach: T84 cells, when cultured in monolayers, differentiate to form adult colonic crypt-like cells with excellent permeability barrier properties. The integrity of the permeability barrier in these monolayers was measured using transepithelial electrical resistance (TEER). NAE levels were determined by ultra-performance liquid chromatography-tandem mass spectrometric analysis. Expression of the enzymes involved in NAE and 2-arachidonoylglycerol (2-AG) turnover were assessed with qPCR.Key Results: IFNγ treatment for 8 or 24 h increased levels of both endocannabinoids (anandamide and 2-AG) and the related NAEs. The treatment did not affect the rate of hydrolysis of either anandamide or palmitoylethanolamide by intact cells, and in both cases, fatty acid amide hydrolase (FAAH) rather than NAE-hydrolysing acid amidase (NAAA) was mainly responsible for the hydrolysis of these NAEs. IFNγ treatment reduced the TEER of the cells in a manner that was not prevented by inhibition of either FAAH or NAAA but was partially reversed by apical administration of the NAE palmitoylethanolamide.Conclusion and Implications: IFNγ treatment mobilized endocannabinoid and related NAE levels in T84 cells. However, blockade of anandamide or NAE hydrolysis was insufficient to negate the deleterious effects of this cytokine upon the permeability barrier of the cell monolayers.Linked Articles: This article is part of a themed section on 8th European Workshop on Cannabinoid Research. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.10/issuetoc. [ABSTRACT FROM AUTHOR]

Background and Purpose: An alteration in the communication between the innate and adaptive immune cells is a hallmark of ulcerative colitis (UC). Semaphorin-3E (SEMA3E), a secreted guidance protein, regulates various immune responses.Experimental Approach: We investigated the expression of SEMA3E in colonic biopsies of active UC patients and its mechanisms in Sema3e-/- mice using an experimental model of UC.Key Results: SEMA3E level was decreased in active UC patients and negatively correlated with pro-inflammatory mediators. Colonic expression of SEMA3E was reduced in colitic Sema3e+/+ mice, and recombinant (rec-) Plexin-D1 treatment exacerbated disease severity. In vivo rec-SEMA3E treatment restored SEMA3E level in colitic Sema3e+/+ mice. In Sema3e-/- mice, disease severity was increased, and rec-SEMA3E ameliorated these effects. Lack of Sema3e increased the expression of CD11c and CD86 markers. Colitic Sema3e-/- splenocytes and splenic CD11c+ cells produced more IL-12/23 and IFN-γ compared to Sema3e+/+ , and rec-SEMA3E reduced their release as much as NF-κB inhibitors, whereas an NF-κB activator increased their production and attenuated the effect of rec-SEMA3E. Colitic Sema3e-/- splenic CD11c+ /CD4+ CD25- T-cell co-cultures produced higher concentrations of IFN-γ and IL-17 when compared to colitic Sema3e+/+ splenic cell co-cultures, and rec-SEMA3E decreased these effects. In vitro, anti-IL-12p19 and -12p35 antibodies and rec-IL-12 and -23 treatment confirmed the crosstalk between CD11c+ and CD4+ CD25- T-cells.Conclusion and Implications: SEMA3E is reduced in colitis and modulates colonic inflammation by regulating the interaction between CD11c+ and CD4+ CD25- T-cells via an NF-κB-dependent mechanism. Thus, SEMA3E could be a potential therapeutic target for UC patients. [ABSTRACT FROM AUTHOR]

The metzincin clan of metalloproteinases includes the MMP, disintegrin and metalloproteinase (ADAM) and ADAM with thrombospondin motifs families, which cleave extracellular targets in a wide range of (patho)physiological processes. Antibodies constitute a powerful tool to modulate the activity of these enzymes for both therapeutic and research purposes. In this review, we give an overview of monoclonal antibodies (mAbs) that have been tested in preclinical disease models, human trials and important studies of metzincin structure and function. Initial attempts to develop therapeutic small molecule inhibitors against MMPs were hampered by structural similarities between metzincin active sites and, consequently, off-target effects. Therefore, more recently, mAbs have been developed that do not bind to the active site but bind to surface-exposed loops that are poorly conserved in closely related family members. Inhibition of protease activity by these mAbs occurs through a variety of mechanisms, including (i) barring access to the active site, (ii) disruption of exosite binding, and (iii) prevention of protease activation. These different modes of inhibition are discussed in the context of the antibodies' potency, selectivity and, importantly, the effects in models of disease and clinical trials. In addition, various innovative strategies that were used to generate anti-metzincin mAbs are discussed. LINKED ARTICLES: This article is part of a themed section on Translating the Matrix. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.1/issuetoc. [ABSTRACT FROM AUTHOR]

Background and Purpose: The pleiotropic properties of HDL may exert beneficial effects on the myocardium. The effect of recombinant HDLMilano on established heart failure was evaluated in C57BL/6 mice.Experimental Approach: Mice were subjected to transverse aortic constriction (TAC) or sham operation at the age of 14 weeks. Eight weeks later, TAC and sham mice were each randomized into three different groups. Reference groups were killed at day 56 after the operation for baseline analysis. Five i.p. injections of recombinant HDLMilano (MDCO-216), 100 mg·kg-1 , or an equivalent volume of control buffer were administered with a 48 h interval starting at day 56. Endpoint analyses in the control buffer groups and in the MDCO-216 groups were executed at day 65.Key Results: Lung weight in MDCO-216 TAC mice was 25.3% lower than in reference TAC mice and 27.9% lower than in control buffer TAC mice and was similar in MDCO-216 sham mice. MDCO-216 significantly decreased interstitial fibrosis and increased relative vascularity compared to reference TAC mice and control buffer TAC mice. The peak rate of isovolumetric relaxation in MDCO-216 TAC mice was 30.4 and 36.3% higher than in reference TAC mice and control buffer TAC mice respectively. Nitro-oxidative stress and myocardial apoptosis were significantly reduced in MDCO-216 TAC mice compared to control buffer TAC mice.Conclusions and Implications: MDCO-216 improves diastolic function, induces regression of interstitial fibrosis and normalizes lung weight in mice with established heart failure. Recombinant HDL may emerge as a treatment modality in heart failure. [ABSTRACT FROM AUTHOR]

Background and Purpose: Carvedilol is a clinically effective β-blocker broadly used for treating congestive heart failure (CHF), and several clinical trials have demonstrated that it shows a favourable effect compared with other β-blockers in patients with CHF. The mechanism underlying this beneficial effect of carvedilol compared to other β-blockers is not clearly understood. In addition to β-blockers, inhibitors of hyperpolarization-activated cyclic nucleotide (HCN)-gated channels, which play a critical role in spontaneous rhythmic activity in the heart, have also been proposed to be suitable drugs for reducing heart rate and, therefore, beneficial for treating CHF. In the present study, we investigated the effect of carvedilol on HCN channels.Experimental Approach: Whole-cell patch-clamp recordings were used to assess the effect of carvedilol on currents from wild-type and mutant HCN1, HCN2 and HCN4 channels expressed in CHO cells.Key Results: Carvedilol was the only β-blocker tested that showed inhibitory effects on the major sinoatrial HCN channel isoform HCN4. Carvedilol inhibited HCN4 in a concentration-dependent manner with an EC50 of 4.4 μM. In addition, carvedilol also inhibited HCN1 and HCN2 channels. Carvedilol blocked HCN channels by decelerating the rate of channel activation and increasing that of deactivation, and shifted the voltage-dependence of activation leftwards. Our data also showed that carvedilol, unlike other inhibitors of this channel (ivabradine and ZD7288), is not an 'open-channel' inhibitor of HCN4.Conclusions and Implications: Carvedilol is a negative gating modulator of HCN channels. It represents a novel structure for future drug design of HCN channel inhibitors. [ABSTRACT FROM AUTHOR]