The effect of vortioxetine on penicillin-induced epileptiform activity in rats

The effect of Vortioxetine on the NLRP3 pathway and microglial activity in the prefrontal cortex in an experimental model of depression

BACKGROUND

Increasing evidence suggests that early life stress (ELS) and neuroinflammation are associated with the pathophysiology of depression. The purpose of this study was to determine the effects of Vortioxetine (VOR), a novel antidepressant, on ELS-induced behavioral changes and neuroinflammation.

METHOD

Wistar Albino 4-week-old male rats were divided into four groups: control; chronic unpredictable stress (CUMS), VOR, CUMS + VOR. Neurobehavioral assessment was performed on the first, 21st, and 42nd days. RT-PCR was used to detect the expression of P2X7, NLRP3, IL1β, IL18 in the prefrontal cortex. To assess the microglial activities of the prefrontal cortex, immunohistochemically stained CD68, and leukocyte common antigen (LCA) preparations were scanned with Manual WSI software, Basler camera, and scored.

RESULT AND DISCUSSION

Exposure to CUMS was associated with depression and anxiety-like behaviors, and administration of VOR led to improvement in these behaviors. NLRP3, IL-1β, and IL-18 were shown to be upregulated in the prefrontal cortex of CUMS rats, while their high expression was inhibited by VOR treatment. CD68 and LCA expressions were significantly higher in the CUMS group compared to the other groups.

CONCLUSION

According to these results, it may be considered that NLRP3 inflammasome-associated neuroinflammatory response and microglial activation may play a role in the etiopathogenesis of ELS.

Anesthesia and analgesia for experimental craniotomy in mice and rats: a systematic scoping review comparing the years 2009 and 2019

Experimental craniotomies are a common surgical procedure in neuroscience. Because inadequate analgesia appears to be a problem in animal-based research, we conducted this review and collected information on management of craniotomy-associated pain in laboratory mice and rats. A comprehensive search and screening resulted in the identification of 2235 studies, published in 2009 and 2019, describing craniotomy in mice and/or rats. While key features were extracted from all studies, detailed information was extracted from a random subset of 100 studies/year. Reporting of perioperative analgesia increased from 2009 to 2019. However, the majority of studies from both years did not report pharmacologic pain management. Moreover, reporting of multimodal treatments remained at a low level, and monotherapeutic approaches were more common. Among drug groups, reporting of pre- and postoperative administration of non-steroidal anti-inflammatory drugs, opioids, and local anesthetics in 2019 exceeded that of 2009. In summary, these results suggest that inadequate analgesia and oligoanalgesia are persistent issues associated with experimental intracranial surgery. This underscores the need for intensified training of those working with laboratory rodents subjected to craniotomies.

Systematic review registration

https://osf.io/7d4qe.

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).

The antiinflammatory and electrophysiological effects of fingolimod on penicillin-induced rats

BACKGROUND

The fact that inflammation triggers epileptic seizures brings to mind the antiepileptic properties of anti-inflammatory drugs.

OBJECTIVE

To investigate the electrophysiological and anti-inflammatory effects of fingolimod on an experimental penicillin-induced acute epileptic seizure model in rats.

METHODS

Thirty-two male Wistar rats were divided into four groups: control (penicillin), positive control (penicillin + diazepam [5 mg/kg]), drug (penicillin + fingolimod [0.3 mg/kg]) and synergy group (penicillin + diazepam + fingolimod). The animals were anesthetized with urethane, and epileptiform activity was induced by intracortical injection of penicillin (500,000 IU). After electrophysiological recording for 125 minutes, IL-1β, TNF-α, and IL-6 were evaluated by ELISA in the serum of sacrificed animals.

RESULTS

During the experiment, animal deaths occurred in the synergy group due to the synergistic negative chronotropic effect of diazepam and fingolimod. Although not statistically significant, fingolimod caused a slight decrease in spike-wave activity and spike amplitudes in the acute seizure model induced by penicillin (p > 0.05). Fingolimod decreased serum IL-1β (p < 0.05); fingolimod and diazepam together reduced IL-6 (p < 0.05), but no change was observed in serum TNF-α values.

CONCLUSION

Even in acute use, the spike-wave and amplitude values of fingolimod decrease with diazepam, anticonvulsant and anti-inflammatory effects of fingolimod will be more prominent in chronic applications and central tissue evaluations. In addition, concomitant use of fingolimod and diazepam is considered to be contraindicated due to the synergistic negative inotropic effect.

Case Report: Vortioxetine in the Treatment of Depressive Symptoms in Patients With Epilepsy-Case Series

Epilepsy and depression are both serious and potentially disabling conditions which often coexist-bidirectional relationship between the two disorders has been observed. Comorbidity between depression and epilepsy can be attributed to: underlying common pathophysiological mechanisms, psychiatric side effect of antiepileptic medications and psychological response to stress in people with chronic, neurological condition. Despite high prevalence of depressive symptoms in patients with epilepsy, current evidence of the effectiveness of antidepressant therapy in this group of patients is very limited. Vortioxetine is an antidepressant with multimodal activity, very good treatment tolerability, low risk of inducing pharmacokinetic interactions, relative safety of treatment in patients with somatic comorbidities, low risk of causing: sedation, sexual dysfunctions and metabolic side effects. Vortioxetine seems to be a promising treatment option for depressed patients with cognitive dysfunctions, anhedonia and anxiety. In this case series, we report nine cases of patients with epilepsy and depressive symptoms treated with vortioxetine. Seven cases are patients with secondary focal and generalized epilepsy and two with unclassified epilepsy. Three patients presented with depressive episode in the course of bipolar disorder and six patients had depressive symptoms due to organic mood disorder. The dose range of vortioxetine was between 10 and 20 mg. In all of the presented cases effectiveness and tolerability of treatment were very good. Remission of depressive symptoms was achieved in all patients. No epilepsy seizures after switch to vortioxetine were observed in seven cases. In two patients seizures occurred during the first months of vortioxetine treatment but this most probably was due to suboptimal antiepileptic treatment-satisfactory seizure control was achieved after optimization of antiepileptic pharmacotherapy. Vortioxetine was discontinued in two of the presented cases due to pregnancy planning. The duration of observation period during vortioxetine therapy ranged from 2 to 48 months. In conclusion, vortioxetine can be a promising treatment option in patients with epilepsy and comorbid depressive symptoms.

5-HT1A Serotonergic, α-Adrenergic and Opioidergic Receptors Mediate the Analgesic Efficacy of Vortioxetine in Mice

Vortioxetine is a multimodal antidepressant drug that affects several brain neurochemicals and has the potential to induce various pharmacological effects on the central nervous system. Therefore, we investigated the centrally mediated analgesic efficacy of this drug and the mechanisms underlying this effect. Analgesic activity of vortioxetine (5, 10 and 20 mg/kg, p.o.) was examined by tail-clip, tail-immersion and hot-plate tests. Motor performance of animals was evaluated using Rota-rod device. Time course measurements (30-180 min) showed that vortioxetine (10 and 20 mg/kg) administrations significantly increased the response latency, percent maximum possible effect and area under the curve values in all of the nociceptive tests. These data pointed out the analgesic effect of vortioxetine on central pathways carrying acute thermal and mechanical nociceptive stimuli. Vortioxetine did not alter the motor coordination of mice indicating that the analgesic activity of this drug was specific. In mechanistic studies, pre-treatments with p-chlorophenylalanine (serotonin-synthesis inhibitor), NAN-190 (serotonin 5-HT_1A receptor antagonist), α-methyl-para-tyrosine (catecholamine-synthesis inhibitor), phentolamine (non-selective α-adrenoceptor blocker), and naloxone (non-selective opioid receptor blocker) antagonised the vortioxetine-induced analgesia. Obtained findings indicated that vortioxetine-induced analgesia is mediated by 5-HT_1A serotonergic, α-adrenergic and opioidergic receptors, and contributions of central serotonergic and catecholaminergic neurotransmissions are critical for this effect.

Vortioxetine increases absence-like seizures in WAG/Rij rats but decreases penicillin- and pentylenetetrazole-induced seizures in Wistar rats

AIM

Depression is the major psychiatric disorder in patients with epilepsy. Vortioxetine is a novel antidepressant drug for the treatment of major depressive disorders. In the present study, effects of vortioxetine were evaluated in different experimental epilepsy models of rats.

MATERIALS AND METHODS

Fifty-six adult male Wistar rats and 28 WAG/Rij rats were divided into 12 groups of 7 rats each. Experiments were conducted with penicillin (500 IU, i.c.) and pentylenetetrazole models (50 mg/kg, intraperitoneally (i.p.)) in Wistar rats and genetic absence epileptic WAG/Rij rats. The vortioxetine (1, 5, or 10 mg/kg, i.p.) was evaluated in these three models. All groups were compared with their control groups.

RESULTS

In the penicillin-induced seizure model, 1, 5, or 10 mg/kg vortioxetine administration significantly decreased mean spike frequency. In the pentylenetetrazole-induced seizure model, 1, 5, or 10 mg/kg vortioxetine demonstrated a significant dose-dependent decrease in mean spike frequency, an increase in the latency to minor and major seizures, and a decrease in total duration of major seizure and convulsion stage. In genetic absence epileptic WAG/Rij rats, 1 mg/kg vortioxetine caused no significant alteration in the number and duration of SWDs compared to the controls, while 5 and 10 mg/kg doses of vortioxetine increased the number and duration of SWDs. Amplitude of the epileptiform activity did not change in any of the experimental epilepsy models.

CONCLUSION

The results of this study suggested that vortioxetine has anticonvulsant activity in penicillin- and pentylenetetrazole-induced seizure models. However, it exhibited proconvulsant activity in the absence epileptic WAG/Rij rats.