Antidepressants in epilepsy

Inhibition of Kv2.1 potassium channels by the antidepressant drug sertraline

Sertraline is a commonly used antidepressant of the selective serotonin reuptake inhibitors (SSRIs) class. In this study, we have used the patch-clamp technique to assess the effects of sertraline on Kv2.1 channels heterologously expressed in HEK-293 cells and on the voltage-gated potassium currents (IKv) of Neuro 2a cells, which are predominantly mediated by Kv2.1 channels. Our results reveal that sertraline inhibits Kv2.1 channels in a concentration-dependent manner. The sertraline-induced inhibition was not voltage-dependent and did not require the channels to be open. The kinetics of activation and deactivation were accelerated and decelerated, respectively, by sertraline. Moreover, the inhibition by this drug was use-dependent. Notably, sertraline significantly modified the inactivation mechanism of Kv2.1 channels; the steady-state inactivation was shifted to hyperpolarized potentials, the closed-state inactivation was enhanced and accelerated, and the recovery from inactivation was slowed, suggesting that this is the main mechanism by which sertraline inhibits Kv2.1 channels. Overall, this study provides novel insights into the pharmacological actions of sertraline on Kv2.1 channels, shedding light on the intricate interaction between SSRIs and ion channel function.

Pharmacological update of mirtazapine: a narrative literature review

Mirtazapine (MTZ) is an antidepressant drug with an exceptional pharmacological profile. It also has an excellent safety and tolerability profile. The present review provides a pharmacological update on MTZ and summarizes the research findings of MTZ's effects on different diseases. MTZ is hypothesized to have antidepressant effects because of the synergy between noradrenergic and serotonergic actions and is effective in treating major depressive disorder and depression associated with epilepsy, Alzheimer's disease, stroke, cardiovascular disease, and respiratory disease. In cancer patients, MTZ significantly reduced sadness, nausea, sleep disruption, and pain and improved quality of life. Also, it has promising effects on Parkinson's disease, schizophrenia, dysthymia, social anxiety disorder, alcohol dependency, posttraumatic stress disorder, panic disorder, pain syndromes, obsessive-compulsive disorder, and sleep disorders. Additionally, MTZ is potentially therapeutic in different situations associated with depression, such as liver, kidney, cardiovascular, respiratory, infertility, heavy metal-induced neurotoxicity, and pruritus. Potent antioxidative, anti-inflammatory, and anti-apoptotic bioactivities mediate these promising effects. These positive outcomes of the scientific investigations motivate more and more clinical trials for a golden exceptional antidepressant in different conditions.

Clinical side-effects based drug repositioning for anti-epileptic activity

Several generations of anti-epileptic drugs (AEDs) are available but have several associated side effects apart from a limited success rate. Drug repositioning strategies have gained importance in the last two decades owing to lower failure rates and economic burden. Drugs with similar side effect profiles may share a common mechanism of action and thus can be linked to other disease treatments. The present study was carried out to identify the newly approved drug candidate(s) as AEDs using clinical side-effects drug repositioning strategy. The clinical side effect similarity of drugs available in the SIDER v4.1 database was estimated against common side effects of 5 major marketed AEDs, using the 'dplyr' package library in the R. Further drugs were filtered based on Blood Brain Barrier permeability prediction and FDA-approval status. Molecular docking studies were performed for selected 26 hits (drugs) against previously identified epilepsy target receptors: Voltage-gated sodium channel α2 (Nav1.2), GABA receptor α1-β1 (GABAr α1-β1), and Voltage-gated calcium channel α-1 G (Cav3.1). Only 2 drugs (Ziprasidone and Paroxetine) showed better binding affinities against studied epilepsy receptors Nav1.2, GABAr α1-β1, and Cav3.1, than their corresponding standard AEDs, i.e. Carbamazepine, Clonazepam, and Pregabalin, respectively. Ziprasidone reportedly showed seizure-like symptoms in ∼3% of patients and was hence omitted from further study. The MDS study of docked complexes of Paroxetine with selected epilepsy target receptors showed stable RMSD values and better interaction energies. The study reveals Paroxetine as a potential candidate to be repurposed for 1st line epileptic seizure medication.Communicated by Ramaswamy H. Sarma.

In Silico Discovery of Potential Inhibitors Targeting the RNA Binding Loop of ADAR2 and 5-HT2CR from Traditional Chinese Natural Compounds

Adenosine deaminase acting on RNA 2 (ADAR2) is an important enzyme involved in RNA editing processes, particularly in the conversion of adenosine to inosine in RNA molecules. Dysregulation of ADAR2 activity has been implicated in various diseases, including neurological disorders (including schizophrenia), inflammatory disorders, viral infections, and cancers. Therefore, targeting ADAR2 with small molecules presents a promising therapeutic strategy for modulating RNA editing and potentially treating associated pathologies. However, there are limited compounds that effectively inhibit ADAR2 reactions. This study therefore employed computational approaches to virtually screen natural compounds from the traditional Chinese medicine (TCM) library. The shortlisted compounds demonstrated a stronger binding affinity to the ADAR2 (<-9.5 kcal/mol) than the known inhibitor, 8-azanebularine (-6.8 kcal/mol). The topmost compounds were also observed to possess high binding affinity towards 5-HT2CR with binding energies ranging from -7.8 to -12.9 kcal/mol. Further subjecting the top ADAR2-ligand complexes to molecular dynamics simulations and molecular mechanics Poisson-Boltzmann surface area (MM/PBSA) calculations revealed that five potential hit compounds comprising ZINC000014637370, ZINC000085593577, ZINC000042890265, ZINC000039183320, and ZINC000101100339 had favorable binding free energies of -174.911, -137.369, -117.236, -67.023, and -64.913 kJ/mol, respectively, with the human ADAR2 protein. Residues Lys350, Cys377, Glu396, Cys451, Arg455, Ser486, Gln488, and Arg510 were also predicted to be crucial in ligand recognition and binding. This finding will provide valuable insights into the molecular interactions between ADAR2 and small molecules, aiding in the design of future ADAR2 inhibitors with potential therapeutic applications. The potential lead compounds were also profiled to have insignificant toxicities. A structural similarity search via DrugBank revealed that ZINC000039183320 and ZINC000014637370 were similar to naringin and naringenin, which are known adenosine deaminase (ADA) inhibitors. These potential novel ADAR2 inhibitors identified herein may be beneficial in treating several neurological disorders, cancers, viral infections, and inflammatory disorders caused by ADAR2 after experimental validation.

Molecular Docking and Dynamics Simulation Studies Predict Potential Anti-ADAR2 Inhibitors: Implications for the Treatment of Cancer, Neurological, Immunological and Infectious Diseases

Altered RNA editing has been linked to several neurodevelopmental disorders, including autism spectrum disorder (ASD) and intellectual disability, in addition to depression, schizophrenia, some cancers, viral infections and autoimmune disorders. The human ADAR2 is a potential therapeutic target for managing these various disorders due to its crucial role in adenosine to inosine editing. This study applied consensus scoring to rank potential ADAR2 inhibitors after performing molecular docking with AutoDock Vina and Glide (Maestro), using a library of 35,161 compounds obtained from traditional Chinese medicine. A total of 47 compounds were predicted to be good binders of the human ADAR2 and had insignificant toxicity concerns. Molecular dynamics (MD) simulations, including the molecular mechanics Poisson–Boltzmann surface area (MM/PBSA) procedure, also emphasized the binding of the shortlisted compounds. The potential compounds had plausible binding free energies ranging from −81.304 to −1068.26 kJ/mol from the MM/PBSA calculations. ZINC000085511995, a naphthoquinone had more negative binding free energy (−1068.26 kJ/mol) than inositol hexakisphosphate (IHP) [−873.873 kJ/mol], an agonist and a strong binder of ADAR2. The potential displacement of IHP by ZINC000085511995 in the IHP binding site of ADAR2 could be explored for possible deactivation of ADAR2. Bayesian-based biological activity prediction corroborates the neuropharmacological, antineoplastic and antiviral activity of the potential lead compounds. All the potential lead compounds, except ZINC000014612330 and ZINC000013462928, were predicted to be inhibitors of various deaminases. The potential lead compounds also had probability of activity (Pa) > 0.442 and probability of inactivity (Pi) < 0.116 values for treating acute neurologic disorders, except for ZINC000085996580 and ZINC000013462928. Pursuing these compounds for their anti-ADAR2 activities holds a promising future, especially against neurological disorders, some cancers and viral infections caused by RNA viruses. Molecular interaction, hydrogen bond and per-residue decomposition analyses predicted Arg400, Arg401, Lys519, Trp687, Glu689, and Lys690 as hot-spot residues in the ADAR2 IHP binding site. Most of the top compounds were observed to have naphthoquinone, indole, furanocoumarin or benzofuran moieties. Serotonin and tryptophan, which are beneficial in digestive regulation, improving sleep cycle and mood, are indole derivatives. These chemical series may have the potential to treat neurological disorders, prion diseases, some cancers, specific viral infections, metabolic disorders and eating disorders through the disruption of ADAR2 pathways. A total of nine potential lead compounds were shortlisted as plausible modulators of ADAR2.

A Synthetic Overview of Benzoxazines and Benzoxazepines as Anticancer Agents

Benzoxazines and benzoxazepines are nitrogen and oxygen-containing six and seven-membered benzo-fused heterocyclic scaffolds, respectively. Benzoxazepines and benzoxazines are well-known pharmacophores in pharmaceutical chemistry, which are of significant interest and have been extensively studied because of their promising activity against various diseases including their wide range of anticancer activity. Several reports are known for synthesizing benzoxazine and benzoxazepine-based compounds in the literature. Herein this review provides a critical analysis of synthetic strategies towards benzoxazines and benzoxazepines along with various ranges of anticancer activities based on these molecules that have been reported from 2010 onwards. This review also focuses on the structure-activity relationship of the benzoxazine and benzoxazepine scaffolds containing bioactive compounds and describes how the structural modification affects their anticancer activity.

Design, Synthesis, and Pharmacology of New Triazole-Containing Quinolinones as CNS Active Agents

Epilepsy and major depressive disorder are the two of the most common central nervous system (CNS) diseases. Clinicians and patients call for new antidepressants, antiseizure medicines, and in particular drugs for depression and epilepsy comorbidities. In this work, a dozen new triazole-quinolinones were designed, synthesized, and investigated as CNS active agents. All compounds reduced the immobility time significantly during the forced swim test (FST) in mice at the dosage of 50 mg/kg. Compounds 3f-3j gave superior performance over fluoxetine in the FST with more reductions of the immobility time. Compound 3g also reduced immobility time significantly in a tail suspension test (TST) at the dosage of 50 mg/kg, though its anti-immobility activity was inferior to that of fluoxetine. An open field test was carried out and it eliminated the false-positive possibility of 3g in the FST and TST, which complementarily supported the antidepressant activity of 3g. We also found that almost all compounds except 3k exhibited antiseizure activity in the maximal electroshock seizure (MES) model at 100 or 300 mg/kg. Compounds 3c, 3f, and 3g displayed the ED₅₀ of 63.4, 78.9, and 84.9 mg/kg, and TD₅₀ of 264.1, 253.5, and 439.9 mg/kg, respectively. ELISA assays proved that the mechanism for the antiseizure and antidepressant activities of compound 3g was via affecting the concentration of GABA in mice brain. The molecular docking study showed a good interaction between 3g and the amino acid residue of the GABA_A receptor. Excellent drug-like properties and pharmacokinetic properties of compound 3a-l were also predicted by Discovery Studio. These findings provided a new skeleton to develop agents for the treatment of epilepsy and depression comorbidities.

Antidepressant Drugs for Seizures and Epilepsy: Where do we Stand?

People with epilepsy (PWE) are more likely to develop depression and both these complex chronic diseases greatly affect health-related quality of life (QOL). This comorbidity contributes to the deterioration of the QOL further than increasing the severity of epilepsy worsening prognosis. Strong scientific evidence suggests the presence of shared pathogenic mechanisms. The correct identification and management of these factors are crucial in order to improve patients' QOL. This review article discusses recent original research on the most common pathogenic mechanisms of depression in PWE and highlights the effects of antidepressant drugs (ADs) against seizures in PWE and animal models of seizures and epilepsy. Newer ADs, such as selective serotonin reuptake inhibitors (SRRI) or serotonin-noradrenaline reuptake inhibitors (SNRI), particularly sertraline, citalopram, mirtazapine, reboxetine, paroxetine, fluoxetine, escitalopram, fluvoxamine, venlafaxine, duloxetine may lead to improvements in epilepsy severity whereas the use of older tricyclic antidepressant (TCAs) can increase the occurrence of seizures. Most of the data demonstrate the acute effects of ADs in animal models of epilepsy while there is a limited number of studies about the chronic antidepressant effects in epilepsy and epileptogenesis or on clinical efficacy. Much longer treatments are needed in order to validate the effectiveness of these new alternatives in the treatment and the development of epilepsy, while further clinical studies with appropriate protocols are warranted in order to understand the real potential contribution of these drugs in the management of PWE (besides their effects on mood).

Physical exercise and mitochondrial function: New therapeutic interventions for psychiatric and neurodegenerative disorders

Psychiatric and neurodegenerative diseases, including major depression disorder (MDD), bipolar disorder, and Alzheimer's disease, are a burden to society. Deficits of adult hippocampal neurogenesis (AHN) have been widely considered the main hallmark of psychiatric diseases as well as neurodegeneration. Herein, exploring applicable targets for improving hippocampal neural plasticity could provide a breakthrough for the development of new treatments. Emerging evidence indicates the broad functions of mitochondria in regulating cellular behaviors of neural stem cells, neural progenitors, and mature neurons in adulthood could offer multiple neural plasticities for behavioral modulation. Normalizing mitochondrial functions could be a new direction for neural plasticity enhancement. Exercise, a highly encouraged integrative method for preventing disease, has been indicated to be an effective pathway to improving both mitochondrial functions and AHN. Herein, the relative mechanisms of mitochondria in regulating neurogenesis and its effects in linking the effects of exercise to neurological diseases requires a systematic summary. In this review, we have assessed the relationship between mitochondrial functions and AHN to see whether mitochondria can be potential targets for treating neurological diseases. Moreover, as for one of well-established alternative therapeutic approaches, we summarized the evidence to show the underlying mechanisms of exercise to improve mitochondrial functions and AHN.

Response to sertraline and antiepileptic drugs in pentylenetetrazole kindling in rats

Anti-epileptic drugs (AEDs) are the mainstay of epilepsy treatment but these may be a potential risk factor for behavioral disturbances particularly depression which requires treatment. In this study, the effect of antidepressant sertraline (SRT) in combination with AEDs sodium valproate (SV) and levetiracetam (LEV) on seizures, cognitive impairment and oxidative stress in rats was evaluated. After administration of 24th injection of pentylenetetrazole (PTZ), 77.8% rats were kindled. Administration of SRT showed no protective effect on kindling development while SV was 100% protective. With LEV 42.9% were kindled. On combining SRT with SV or LEV 25% and 20% rats were kindled. A significant increase in latency to reach platform zone in Morris water maze(MWM), and increased transfer latencies in Elevated plus maze(EPM) was observed in PTZ kindled rats as compared to normal control on day 49 and when LEV was combined with SRT. In EPM test, however none of the drug treatments had any effect on transfer latencies except LEV pretreated kindled group. In Passive avoidance (PA) test, kindling was associated with a significant decrease in retention time(p = 0.018) while LEV and SV had no effect. The PTZ kindled rats showed significantly higher malondialdehyde(MDA) levels in brain hippocampus(p = 0.0286) while both SRT and SV were associated with significantly lower MDA levels as compared to kindled control group. In case of glutathione (GSH), kindling had no significant effect. The use of sertraline for depression in persons with epilepsy on AEDs needs to be carefully evaluated and monitored due to likelihood of individual variation.

1,5-Benzoxazepines as a unique and potent scaffold for activity drugs: A review

Benzoxazepines constitute a huge number of organic compounds widely described in the literature. Many of them are distinguished by their biological properties. Among them, our attention was drawn to 1,5-benzoxazepine derivatives due to their interesting pharmacological properties. As is reported in the literature, these compounds are not only good building blocks in organic synthesis but also have interesting biological and pharmacological properties. This article is the first review publication to describe the synthesis methods and unique properties of 1,5-benzoxazepines. Literature reports widely describe the biological properties of 1,5-benzoxazepine, like anticancer, antibacterial, or antifungal activities. 1,5-Benzoxazepine derivatives can also interact with G-protein-coupled receptors and could be incorporated into new potential drugs, among others, in treating neuronal disorders like Alzheimer's and Parkinson's disease.

Multipronged Attack of Stem Cell Therapy in Treating the Neurological and Neuropsychiatric Symptoms of Epilepsy

Epilepsy stands as a life-threatening disease that is characterized by unprovoked seizures. However, an important characteristic of epilepsy that needs to be examined is the neuropsychiatric aspect. Epileptic patients endure aggression, depression, and other psychiatric illnesses. Therapies for epilepsy can be divided into two categories: antiepileptic medications and surgical resection. Antiepileptic drugs are used to attenuate heightened neuronal firing and to lessen seizure frequency. Alternatively, surgery can also be conducted to physically cut out the area of the brain that is assumed to be the root cause for the anomalous firing that triggers seizures. While both treatments serve as viable approaches that aim to regulate seizures and ameliorate the neurological detriments spurred by epilepsy, they do not serve to directly counteract epilepsy's neuropsychiatric traits. To address this concern, a potential new treatment involves the use of stem cells. Stem cell therapy has been employed in experimental models of neurological maladies, such as Parkinson's disease, and neuropsychiatric illnesses like depression. Cell-based treatments for epilepsy utilizing stem cells such as neural stem cells (NSCs), mesenchymal stem cells (MSCs), and interneuron grafts have been explored in preclinical and clinical settings, highlighting both the acute and chronic stages of epilepsy. However, it is difficult to create an animal model to capitalize on all the components of epilepsy due to the challenges in delineating the neuropsychiatric aspect. Therefore, further preclinical investigation into the safety and efficacy of stem cell therapy in addressing both the neurological and the neuropsychiatric components of epilepsy is warranted in order to optimize cell dosage, delivery, and timing of cell transplantation.

Emotion and mood disorders associated with epilepsy

Epilepsy is a disorder characterized by recurrent seizures. Epilepsy can alter mood and emotions. Treatments for epilepsy can also alter mood and emotions. This chapter reviews the emotional changes that can occur before, during, and after a seizure, such as fear and anger, the interictal mood disorders associated with epilepsy, such as depression and anxiety, as well as alterations of emotional processing including comprehending and expressing emotional prosody and faces. The possible treatments of these emotional and mood disorders are also reviewed.

Drug Treatment of Epilepsy Neuropsychiatric Comorbidities in Children

There is increasing recognition that epilepsy can be associated with a broad spectrum of comorbidities. While epileptic seizures are an essential element of epilepsy in children, there is a spectrum of neurological, mental health and cognitive disorders that add to the disease burden of childhood epilepsy resulting in a decreased quality of life. The most common comorbid conditions in childhood epilepsy include depression, anxiety, autism spectrum disorders, sleep disorders, attention deficits, cognitive impairment, and migraine. While epilepsy can result in comorbidities, many of the comorbidities of childhood have a bi-directional association, with the comorbid condition increasing risk for epilepsy and epilepsy increasing the risk for the comorbid condition. The bidirectional feature of epilepsy and the comorbidities suggest a common underlying pathological basis for both the seizures and comorbid condition. While recognition of the comorbid conditions of pediatric epilepsies is increasing, there has been a lag in the development of effective therapies partly out of concern that drugs used to treat the comorbid conditions could increase seizure susceptibility. There is now some evidence that most drugs used for comorbid conditions are safe and do not lower seizure threshold. Unfortunately, the evidence showing drugs are effective in treating many of the childhood comorbidities of epilepsy is quite limited. There is a great need for randomized, placebo-controlled drug trials for efficacy and safety in the treatment of comorbidities of childhood epilepsy.

Anxiety disorders and medical illness comorbidity and treatment implications

PURPOSE OF REVIEW

To review recent studies which assess comorbidity, that is, prevalence of co-occurrence, relationships and treatment implications between anxiety disorders and various medical illnesses.

RECENT FINDINGS

The prevalence rates of anxiety disorders in patients with medical illnesses are high, with percentage up to 29% in patients with epilepsy, 48.9% in patients with multiple sclerosis, 30.1% in patients with Parkinson's disease, 30% in patients with cardiovascular disease, 47.0% in patients with diabetes mellitus, and so on. The most prevalent anxiety disorders among individuals with somatic illnesses are generalized anxiety disorder and panic disorder. In addition, various medical illnesses are highly prevalent in samples of patients with anxiety disorders. Anxiety disorders co-occurring with medical illnesses have a number of clinical implications, including a greater severity and negative impact on treatment outcome of both medical illnesses and anxiety disorders.

SUMMARY

It is important for clinicians to look for possible anxiety disorders among patients with medical illnesses. Further studies need to ascertain how to best treat individuals suffering from both anxiety disorders and medical illnesses, and focus on the issue of causality when these conditions co-occur.