Perspectives on treatment options for mesial temporal lobe epilepsy with hippocampal sclerosis

INTRODUCTION

Mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS) is a syndrome that is often refractory to drug treatment. The effects on specific syndromes are not currently available from the pre-marketing clinical development of new AEDs; this does not allow the prediction of whether new drugs will be more effective in the treatment of some patients.

AREAS COVERED

We have reviewed all the existing literature relevant to the understanding of a potential effectiveness in MTLE-HS patients for the latest AEDs, namely brivaracetam, eslicarbazepine, lacosamide, perampanel and retigabine also including the most relevant clinical data and a brief description of their pharmacological profile. Records were identified using predefined search criteria using electronic databases (e.g., PubMed, Cochrane Library Database of Systematic Reviews). Primary peer-reviewed articles published up to the 15 June 2015 were included.

EXPERT OPINION

All the drugs considered have the potential to be effective in the treatment of MTLE-HS; in fact, they possess proven efficacy in animal models; currently considered valuable tools for predicting drug efficacy in TLE. Furthermore, for some of these (e.g., lacosamide and eslicarbazepine) data are already available from post-marketing studies while brivaracetam acting on SV2A like levetiracetam might have the same potential effectiveness with the possibility to be more efficacious considering its ability to inhibit voltage gated sodium channels; finally, perampanel and retigabine are very effective drugs in animal models of TLE.

Magnetic resonance imaging-quantified small bowel motility is a sensitive marker of response to medical therapy in Crohn's disease

BACKGROUND

Magnetic resonance enterography (MRE) can measure small bowel motility, reduction in which reflects inflammatory burden in Crohn's Disease (CD). However, it is unknown if motility improves with successful treatment.

AIM

To determine if changes in segmental small bowel motility reflect response to anti-TNFα therapy after induction and longer term.

METHODS

A total of 46 patients (median 29 years, 19 females) underwent MRE before anti-TNFα treatment; 35 identified retrospectively underwent repeat MRE after median 55 weeks of treatment and 11 recruited prospectively after median 12 weeks. Therapeutic response was defined by physician global assessment (retrospective group) or a ≥3 point drop in the Harvey-Bradshaw Index (prospective group), C-reactive protein (CRP) and the MaRIA score. Two independent radiologists measured motility using an MRE image-registration algorithm. We compared motility changes in responders and nonresponders using the Mann-Whitney test.

RESULTS

Anti-TNFα responders had significantly greater improvements in motility (median = 73.4% increase from baseline) than nonresponders (median = 25% reduction, P < 0.001). Improved MRI-measured motility was 93.1% sensitive (95%CI: 78.0-98.1%) and 76.5% specific (95% CI: 52.7-90.4%) for anti-TNFα response. Patients with CRP normalisation (<5 mg/L) had significantly greater improvements in motility (median = 73.4% increase) than those with persistently elevated CRP (median = 5.1%, P = 0.035). Individuals with post-treatment MaRIA scores of <11 had greater motility improvements (median = 94.7% increase) than those with post-treatment MaRIA score >11 (median 15.2% increase, P = 0.017).

CONCLUSIONS

Improved MRI-measured small bowel motility accurately detects response to anti-TNFα therapy for Crohn's disease, even as early as 12 weeks. Motility MRI may permit early identification of nonresponse to anti-TNFα agents, allowing personalised treatment.

Classical and non-classical proangiogenic factors as a target of antiangiogenic therapy in tumor microenvironment

Angiogenesis is sustained by classical and non-classical proangiogenic factors (PFs) acting in tumor microenvironment and these factors are also potential targets of antiangiogenic therapies. All PFs induce the overexpression of several signaling pathways that lead to migration and proliferation of endothelial cells contributing to tumor angiogenesis and survival of cancer cells. In this review, we have analyzed each PF with its specific receptor/s and we have summarized the available antiangiogenic drugs (e.g. monoclonal antibodies) targeting these PFs, some of these agents have already been approved, others are currently in development for the treatment of several human malignancies.

Peroxisome proliferator-activated receptor alpha plays a crucial role in behavioral repetition and cognitive flexibility in mice

Background/objectives

Nuclear peroxisome proliferator activated receptor-α (PPAR-α) plays a fundamental role in the regulation of lipid homeostasis and is the target of medications used to treat dyslipidemia. However, little is known about the role of PPAR-α in mouse behavior.

Methods

To investigate the function of Ppar-α in cognitive functions, a behavioral phenotype analysis of mice with a targeted genetic disruption of Ppar-α was performed in combination with neuroanatomical, biochemical and pharmacological manipulations. The therapeutic exploitability of PPAR-α was probed in mice using a pharmacological model of psychosis and a genetic model (BTBR T + tf/J) exhibiting a high rate of repetitive behavior.

Results

An unexpected role for brain Ppar-α in the regulation of cognitive behavior in mice was revealed. Specifically, we observed that Ppar-α genetic perturbation promotes rewiring of cortical and hippocampal regions and a behavioral phenotype of cognitive inflexibility, perseveration and blunted responses to psychomimetic drugs. Furthermore, we demonstrate that the antipsychotic and autism spectrum disorder (ASD) medication risperidone ameliorates the behavioral profile of Ppar-α deficient mice. Importantly, we reveal that pharmacological PPAR-α agonist treatment in mice improves behavior in a pharmacological model of ketamine-induced behavioral dysinhibition and repetitive behavior in BTBR T + tf/J mice.

Conclusion

Our data indicate that Ppar-α is required for normal cognitive function and that pharmacological stimulation of PPAR-α improves cognitive function in pharmacological and genetic models of impaired cognitive function in mice. These results thereby reveal an unforeseen therapeutic application for a class of drugs currently in human use.

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The lipid nuclear receptor PPAR-α is required for normal cognitive function in mice.

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Genetic ablation of Ppar-α promotes repetitive behavior and cognitive inflexibility in mice.

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Pharmacological stimulation of PPAR-α improves behaviors in models of impaired cognition and enhanced repetitive behavior.

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Our findings suggest Ppar-α as a possible point of commonality between behavioral and metabolic dysfunctions.

Abatacept improves whole-body insulin sensitivity in rheumatoid arthritis: an observational study

Rheumatoid arthritis (RA) is characterized by increased insulin resistance, a well-known risk factor for diabetes and cardiovascular diseases. The aim of the present study was to evaluate the effect of abatacept on insulin sensitivity in RA patients with moderate to severe disease despite treatment with methotrexate. Fifteen RA patients were recruited for the present study. Patients were evaluated at time 0 and after 6 months of the treatment with i.v. abatacept at the dosage recommended for weight range. Evaluation included oral glucose tolerance test (OGTT) at both time points. Insulin sensitivity was estimated with insulin sensitivity index (ISI) by Matsuda, a measure of whole-body insulin sensitivity. ISI significantly increased after the treatment with abatacept from 3.7 ± 2.6 to 5.0 ± 3.2 (P = 0.003) with a mean difference of 1.23. Analysis of glucose and insulin values during OGTT revealed a reduction of both glucose (303.9 ± 73.4 mg/dL min versus 269.2 ± 69.5 mg/dL min, P = 0.009) and insulin (208.4 ± 119.7 mg/dL min versus 158.0 ± 95.3 mg/dL min, P = 0.01) area under the curves (AUCs). Accordingly also glycated hemoglobin significantly improved (5.5 ± 0.4% versus 5.3 ± 0.3%, P = 0.04). No significant differences were found for measures of β-cell function insulinogenic index (1.11 ± 1.19 versus 1.32 ± 0.82, P = 0.77) and oral disposition index (2.0 ± 5.4 versus 6.0 ± 6.0, P = 0.25). Treatment with abatacept seems to be able to improve whole-body insulin sensitivity in RA patients without affecting β-cell function.

Antidepressants but not antipsychotics have antiepileptogenic effects with limited effects on comorbid depressive-like behaviour in the WAG/Rij rat model of absence epilepsy

BACKGROUND AND PURPOSE

Two of the most relevant unmet needs in epilepsy are represented by the development of disease-modifying drugs able to affect epileptogenesis and/or the study of related neuropsychiatric comorbidities. No systematic study has investigated the effects of chronic treatment with antipsychotics or antidepressants on epileptogenesis. However, such drugs are known to influence seizure threshold.

EXPERIMENTAL APPROACH

We evaluated the effects of an early long-term treatment (ELTT; 17 weeks), started before seizure onset (P45), with fluoxetine (selective 5-HT-reuptake inhibitor), duloxetine (dual-acting 5-HT-noradrenaline reuptake inhibitor), haloperidol (typical antipsychotic drug), risperidone and quetiapine (atypical antipsychotic drugs) on the development of absence seizures and comorbid depressive-like behaviour in the WAG/Rij rat model. Furthermore, we studied the effects of these drugs on established absence seizures in adult (6-month-old) rats after a chronic 7 weeks treatment.

KEY RESULTS

ELTT with all antipsychotics did not affect the development of seizures, whereas, both ELTT haloperidol (1 mg · kg(-1) day(-1)) and risperidone (0.5 mg · kg(-1) day(-1)) increased immobility time in the forced swimming test and increased absence seizures only in adult rats (7 weeks treatment). In contrast, both fluoxetine (30 mg · kg(-1) day(-1)) and duloxetine (10-30 mg · kg(-1) day(-1)) exhibited clear antiepileptogenic effects. Duloxetine decreased and fluoxetine increased absence seizures in adult rats. Duloxetine did not affect immobility time; fluoxetine 30 mg · kg(-1) day(-1) reduced immobility time while at 10 mg · kg(-1) day(-1) an increase was observed.

CONCLUSIONS AND IMPLICATIONS

In this animal model, antipsychotics had no antiepileptogenic effects and might worsen depressive-like comorbidity, while antidepressants have potential antiepileptogenic effects even though they have limited effects on comorbid depressive-like behaviour.

Adherence to therapy and adverse drug reactions: is there a link?

INTRODUCTION

Advances in biomedical technology and access to effective medications have resulted in significant improvements in patient survival and quality of life. Patient adherence is crucial to quality healthcare outcomes; however, achievement of consistent adherence remains difficult. Patient non-adherence represents an important health problem, from a clinical/economic viewpoint, being associated with reduced treatment benefits and significant financial burden. Non-adherence potentially leads to adverse drug events (ADEs), which are generally responsible for poorer health outcomes and avoidable resource misuse. Further, adverse drug reactions (ADRs) exemplify one of the most significant barriers to patients' medication-taking behavior with further detrimental clinical/economic outcomes.

AREAS COVERED

The authors review adherence definitions and its measurement, emphasizing the consequences of the New European Pharmacovigilance Legislation on ADR definition. They analyzed the causes and the clinical/economic consequences of non-adherence and ADEs/ADRs in order to highlight a possible causal link.

EXPERT OPINION

Careful assessment of this harmful relationship is crucial in planning for the interventions needed to improve effectiveness of pharmacological care and to safeguard the sustainability of healthcare systems. Finally, through the 'deactivation' of this link, there will be more chance that advances in healthcare technologies will realize their potential to reduce the burden of chronic illness.

Recurrence of atrial fibrillation after switching from brand to generic atenolol

Beta blockers are the initial treatment for rate control of supraventricular tachyarrhythmia in patients without a history of myocardial infarction or left ventricular dysfunction. In this article we report the recurrence of atrial fibrillation after switching to the generic formulation of atenolol.

Comparative analysis of the treatment of chronic antipsychotic drugs on epileptic susceptibility in genetically epilepsy-prone rats

Antipsychotic drugs (APs) are of great benefit in several psychiatric disorders, but they can be associated with various adverse effects, including seizures. To investigate the effects of chronic antipsychotic treatment on seizure susceptibility in genetically epilepsy-prone rats, some APs were administered for 7 weeks, and seizure susceptibility (audiogenic seizures) was evaluated once a week during treatment and for 5 weeks after drug withdrawal. Furthermore, acute and subchronic (5-day treatment) effects were also measured. Rats received haloperidol (0.2-1.0 mg/kg), clozapine (1-5 mg/kg), risperidone (0.03-0.50 mg/kg), quetiapine (2-10 mg/kg), aripriprazole (0.2-1.0 mg/kg), and olanzapine (0.13-0.66 mg/kg), and tested according to treatment duration. Acute administration of APs had no effect on seizures, whereas, after regular treatment, aripiprazole reduced seizure severity; haloperidol had no effects and all other APs increased seizure severity. In chronically treated rats, clozapine showed the most marked proconvulsant effects, followed by risperidone and olanzapine. Quetiapine and haloperidol had only modest effects, and aripiprazole was anticonvulsant. Finally, the proconvulsant effects lasted at least 2-3 weeks after treatment suspension; for aripiprazole, a proconvulsant rebound effect was observed. Taken together, these results indicate and confirm that APs might have the potential to increase the severity of audiogenic seizures but that aripiprazole may exert anticonvulsant effects. The use of APs in patients, particularly in patients with epilepsy, should be monitored for seizure occurrence, including during the time after cessation of therapy. Further studies will determine whether aripiprazole really has a potential as an anticonvulsant drug and might also be clinically relevant for epileptic patients with psychiatric comorbidities.

Profile of brivaracetam and its potential in the treatment of epilepsy

Brivaracetam (BRV) (UCB 34714) is currently under review by the US Food and Drug Administration and European Medicines Agency for approval as an add-on treatment for adult patients with partial seizures. Similar to levetiracetam (LEV), BRV acts as a high-affinity ligand of the synaptic vesicle protein 2A, however, it has been shown to be 10- to 30-fold more potent than LEV. Moreover, BRV does not share the LEV inhibitory activity on the high voltage Ca(2+) channels and AMPA receptors, and it has been reported to act as a partial antagonist on neuronal voltage-gated sodium channels. The pharmacokinetic profile of BRV is favorable and linear, and it undergoes an extensive metabolism into inactive compounds, mainly through the hydrolysis of its acetamide group. Furthermore, it does not significantly interact with other antiepileptic drugs and more than 95% is excreted through the urine, with an unchanged fraction of 8%-11%. BRV has a half-life of approximately 8-9 hours and it is usually given twice daily. To date, a wide range of experimental studies have reported the effectiveness of BRV with regards to partial and generalized seizures. In humans, six randomized, placebo-controlled trials and two meta-analyses highlighted the efficacy, or good tolerability, of BRV as an add-on treatment for patients with uncontrolled partial seizures. A wide dose range of BRV has been evaluated in those trials (5-200 mg), but the most suitable for clinical use appears to be 50-100 mg/day. The most common adverse reactions to BRV are mild to moderate, transient, often improve during the course of the treatment, and mainly consist of central nervous system symptoms, such as fatigue, dizziness, and somnolence. The aim of this paper is to critically review the literature data regarding experimental animal models and clinical trials on BRV, and to define its potential usefulness for the clinicians who manage patients with epilepsy.

Rare and very rare adverse effects of clozapine

Clozapine (CLZ) is the drug of choice for the treatment of resistant schizophrenia; however, its suitable use is limited by the complex adverse effects' profile. The best-described adverse effects in the literature are represented by agranulocytosis, myocarditis, sedation, weight gain, hypotension, and drooling; nevertheless, there are other known adverse effects that psychiatrists should readily recognize and manage. This review covers the "rare" and "very rare" known adverse effects of CLZ, which have been accurately described in literature. An extensive search on the basis of predefined criteria was made using CLZ and its combination with adverse effects as keywords in electronic databases. Data show the association between the use of CLZ and uncommon adverse effects, including ischemic colitis, paralytic ileus, hematemesis, gastroesophageal reflux disease, priapism, urinary incontinence, pityriasis rosea, intertriginous erythema, pulmonary thromboembolism, pseudo-pheochromocytoma, periorbital edema, and parotitis, which are influenced by other variables including age, early diagnosis, and previous/current pharmacological therapies. Some of these adverse effects, although unpredictable, are often manageable if promptly recognized and treated. Others are serious and potentially life-threatening. However, an adequate knowledge of the drug, clinical vigilance, and rapid intervention can drastically reduce the morbidity and mortality related to CLZ treatment.

Effects of chronic sodium alendronate on depression and anxiety in a menopausal experimental model

OBJECTIVE

During menopause, lower levels of estrogen may induce bone resorption as well as anxiety and depression. Bisphosphonates represent the first choice in the treatment of osteoporosis and no data are available concerning their effects on comorbid behavior alterations. Therefore, in this study, we evaluated the effects of chronic alendronate (1 mg/kg/day) on depression and anxiety in an experimental animal model of menopause.

METHODS

Female Wistar rats were ovariectomized or sham operated at 6-7 months of age. Two weeks after surgery, rats were randomized into four treatment (24 consecutive weeks) groups: (1) vehicle-treated SHAM group, (2) alendronate-treated SHAM group, (3) vehicle-treated ovariectomized group, and (4) alendronate-treated ovariectomized group. After treatment, we evaluated both depressive- and anxiety-like behavior through forced swimming test (FST) and open-field test (OF). Finally, the inverted screen test was used to assess the incapacitating effects of ovariectomy in rats.

RESULTS

We documented a significant and time-related increase in immobility times and in anxiety-like behavior in rats with ovariectomy in comparison to control sham group. Alendronate at 3 months, but not at 6 months, significantly decreased both immobility time and anxiety levels, but it significantly increased motor performance. Using the Pearson's test, we documented a significant correlation between behavior and motor performance.

CONCLUSION

Despite the apparent effects of alendronate on animal behavior, in our experiments, such effects seem to be mediated by an increase in motor performance.

Nonpsychotropic plant cannabinoids, cannabidivarin (CBDV) and cannabidiol (CBD), activate and desensitize transient receptor potential vanilloid 1 (TRPV1) channels in vitro: potential for the treatment of neuronal hyperexcitability

Epilepsy is the most common neurological disorder, with over 50 million people worldwide affected. Recent evidence suggests that the transient receptor potential cation channel subfamily V member 1 (TRPV1) may contribute to the onset and progression of some forms of epilepsy. Since the two nonpsychotropic cannabinoids cannabidivarin (CBDV) and cannabidiol (CBD) exert anticonvulsant activity in vivo and produce TRPV1-mediated intracellular calcium elevation in vitro, we evaluated the effects of these two compounds on TRPV1 channel activation and desensitization and in an in vitro model of epileptiform activity. Patch clamp analysis in transfected HEK293 cells demonstrated that CBD and CBDV dose-dependently activate and rapidly desensitize TRPV1, as well as TRP channels of subfamily V type 2 (TRPV2) and subfamily A type 1 (TRPA1). TRPV1 and TRPV2 transcripts were shown to be expressed in rat hippocampal tissue. When tested on epileptiform neuronal spike activity in hippocampal brain slices exposed to a Mg(2+)-free solution using multielectrode arrays (MEAs), CBDV reduced both epileptiform burst amplitude and duration. The prototypical TRPV1 agonist, capsaicin, produced similar, although not identical effects. Capsaicin, but not CBDV, effects on burst amplitude were reversed by IRTX, a selective TRPV1 antagonist. These data suggest that CBDV antiepileptiform effects in the Mg(2+)-free model are not uniquely mediated via activation of TRPV1. However, TRPV1 was strongly phosphorylated (and hence likely sensitized) in Mg(2+)-free solution-treated hippocampal tissue, and both capsaicin and CBDV caused TRPV1 dephosphorylation, consistent with TRPV1 desensitization. We propose that CBDV effects on TRP channels should be studied further in different in vitro and in vivo models of epilepsy.

Satisfaction of patients' next of kin in a 'Hub & Spoke' ICU network

This study aimed to gauge the opinions of patients' next of kin regarding transfer of patients from the specialist 'Hub' intensive care unit, to 'Spoke' intensive care units near home. We included 213 consecutive patients with severe trauma or severe acute neurological conditions admitted to the Hub intensive care unit over a 21-month period, who were repatriated to Spoke intensive care units for ongoing intensive care. One year after admission to the Hub intensive care unit, two thirds of patients' next of kin said they would have preferred patients to have been treated only in the Hub intensive care unit, and not repatriated. They perceived Hub intensive care unit care to be important, and would have preferred that their relatives be hospitalised there until intensive treatment was completed. The next of kin's preference was associated with severe acute neurological conditions (p ≤ 0.0001). Although centralised Hub & Spoke intensive care unit networks are appropriate to ensure specialised care, repatriation to local hospitals may not be appropriate for patients with severe neurological conditions.

Long-term betamethasone 21-phosphate disodium treatment has distinct effects in CD1 and DBA/2 mice on animal behavior accompanied by opposite effects on neurogenesis

One of the most peculiar characteristics of the stress response is the pronounced inter-individual and inter-strain variability both in behavioral and neurochemical outcomes. Several studies confirm that rodents belonging to the same or different strain and/or gender, when exposed to a stressor, may show behavioral and cognitive differences. We compared the effects of long-term betamethasone 21-phosphate disodium (BTM), a widely clinically used corticosteroid, on animal behavior and neurogenesis in CD1 and DBA/2 mice. BTM treatment, in CD1 mice, increased body weight gain and anxiety parameters while having pro-depressant effects. Furthermore, BTM significantly reduced neurogenesis in the dentate gyrus of the hippocampus. Finally, BTM treatment induced a significant impairment in memory and learning performance in the Morris water maze. At odds, BTM administration, in DBA/2 mice, caused a significant reduction in the body weight while not modifying anxiety parameters. In addition, both an increased synaptogenesis and neurogenesis were found. Similarly to CD1 mice, also in DBA/2 mice, memory and learning were impaired. Our data confirm that long-term exposure to corticosteroids can generate or aggravate psychiatric/neurologic disorders such as depression, anxiety, memory and learning. Our study did not reveal significant differences between corticosterone and BTM treatment in CD1 mice. In contrast, BTM treatment in mice with an anxious phenotype (DBA/2 mice) revealed some contrasting results indicating that genetic factors can influence corticosteroids dependent effects. Finally, our data further underline the need for a re-evaluation of neurogenesis role; the increased neurogenesis observed in DBA/2 mice and behavioral effects might be distinguished phenomena.