Evaluation of the Antioxidant Activity of Levetiracetam in a Temporal Lobe Epilepsy Model

Comparing levetiracetam and zonisamide effects on rivastigmine anti-Alzheimer's activity in aluminum chloride-induced Alzheimer's-like disease in rats: Impact on α7 nicotinic acetylcholine receptors and amyloid β

BACKGROUND AND AIM

Alzheimer's disease (AD) is the most progressive form of neurodegenerative disease, which severely impairs cognitive function. The leading class of drugs used to treat AD is acetylcholinesterase inhibitors (AChE-Is) as Rivastigmine (RIVA), partially ameliorate its cognitive symptoms. Since epilepsy is a common comorbidity with AD, we explored the potential that new the antiepileptic drugs; Levetiracetam (LEV) and Zonisamide (ZNS) may possess an additional therapeutic benefit to RIVA in AlCl3-induced AD rat model.

MATERIALS AND METHODS

AlCl3 was used to provoke AD in rats which were then supplemented with treatment drugs for 2 weeks. Treated groups were: Control, AlCl3, RIVA, LEV, RIVA + LEV, ZNS and RIVA + ZNS. Then, the behavioral tests; passive avoidance (PA), Morris water maze (MWM) and novel object recognition (NOR) were conducted to assess cognitive behavior and memory. The Hippocampal Aβ assembly was thoroughly examined by histopathology and ELISA. α7 Nicotinic ACh receptors' (α7nAChRs) expression was assessed immunohistochemically and by real-time quantitative polymerase chain reaction (qPCR). Caspase 3 expression was also assessed by real-time qPCR in hippocampal tissues.

RESULTS

AlCl3 administration impaired memory and cognitive functions in rats, augmented hippocampal Aβ deposition, with subsequent neurodegeneration and α7nAChRs down-regulation. LEV, but not ZNS, administration significantly mitigated AlCl3-induced cognitive impairment probably through suppression of amyloid β (Aβ) deposition, enhancement of neurogenesis and α7nAChRs expression. When combined to RIVA, ZNS treatment negatively affected cognition possibly through its impact on hippocampal Aβ and subsequent neuronal damage.

CONCLUSION

Although our results indicated that neither LEV nor ZNS provided any extra benefit to cognitive enhancements in AD rats receiving rivastigmine, LEV demonstrated positive effects individually while ZNS had negative effects when combined with RIVA. As a result, this study suggests the use of LEV rather than ZNS for managing epilepsy in patients with AD given that Alzheimer's and epilepsy can coexist.

MicroRNAs as Epigenetic Biomarkers of Pathogenetic Mechanisms of the Metabolic Syndrome Induced by Antiseizure Medications: Systematic Review

Antiseizure medication (ASM) induced metabolic syndrome (AIMetS) is a common adverse drug reaction (ADR) of pharmacotherapy for epilepsy and psychiatric disorders. However, the sensitivity and specificity of blood biomarkers may be insufficient due to the influence of combined pathology, concomitant diseases, and the peculiarities of the metabolism of ASMs in patients with epilepsy. Methods: The presented results of experimental and clinical studies of microRNAs (miRs) as epigenetic biomarkers of MetS and AIMetS, which were entered into the different databases, were analyzed for the last decade (2014-2024). Results: A systematic review demonstrated that miRs can act as promising epigenetic biomarkers of key AIMetS domains. However, the results of the review demonstrated the variable role of various miRs and their paralogs in the pathogenesis of AIMetS. Therefore, as part of this study, an miRs signature was proposed that allows us to assess the risk of developing and the severity of AIMetS as low risk, medium risk, and high risk. Conclusions: The mechanisms of development and biomarkers of AIMetS are an actual problem of epileptology, which is still far from being resolved. The development of panels (signatures) of epigenetic biomarkers of this widespread ADR may help to increase the safety of pharmacotherapy of epilepsy. However, to increase the sensitivity and specificity of circulating miRs in the blood as biomarkers of AIMetS, it is necessary to conduct "bridge" studies in order to replicate the results of preclinical and clinical studies into real clinical practice.

Efficacy and acceptability of pharmacological interventions for tardive dyskinesia in people with schizophrenia or mood disorders: a systematic review and network meta-analysis

Tardive Dyskinesia (TD) can occur in people exposed to dopamine receptor antagonists (DRAs). Its clinical management remains challenging. We conducted a systematic review/random-effects network meta-analysis (NMA) searching PubMed/MEDLINE/PsycINFO/ClinicalTrials.gov/Cochrane Central Register (22/05/2023, pre-defined protocol https://osf.io/b52ae/ ), for randomized controlled trials (RCTs) of pharmacological/brain stimulation interventions for DRA-induced TD in adults with schizophrenia or mood disorders. Primary outcomes were TD symptom change (standardized mean difference/SMD) and all-cause discontinuation (acceptability-risk ratio/RR). Sensitivity analyses were conducted. Global, local inconsistencies, risk of bias (RoB-2 tool), and confidence in evidence (CINeMA) were measured. We included 46 trials (n = 2844, age = 52.89 ± 9.94 years, males = 59.8%, schizophrenia = 84.6%, mood disorders = 15.4%), all testing pharmacological interventions versus placebo. We identified three subnetworks. In network 1, several treatments outperformed placebo on TD symptoms with large effect sizes (k = 34, n = 2269), encompassing 22 interventions versus placebo, but 18 had 1 RCTs only, and 15 had n ≤ 20. High heterogeneity (I2 = 57.1%; tau2 = 0.0797), and global inconsistency (Q = 32.64; df = 14; p = 0.0032) emerged. No significant differences emerged in acceptability. When restricting analyses to treatments with trials with n > 20 and >1 RCT, only valbenazine (k = 5, SMD = -0.69; 95% CI = -1.00, -0.37) and vitamin E (k = 7, SMD = -0.49; 95% CI = -0.87, -0.11) were superior to placebo. Deutetrabenazine outperformed placebo considering AIMS score and in low risk of bias trials only and with a moderate effect size for 24/36 mg (k = 2, SMD = -0.57/-0.60). Confidence in findings was low for deutetrabenazine and valbenazine, very low for all others. In network 2 (k = 2, n = 63), switch to molindone (k = 1, n = 9) versus switch to haloperidol worsened TD (SMD = 1.68; 95% CI = 0.61,2.76). In network 3 (k = 3, n = 194), antipsychotic wash-out+placebo (k = 1, n = 25) versus TAU+placebo (k = 1, n = 27) worsened TD (SMD = 1.30; 95% CI = 0.36,2.23). Despite large effect sizes for some treatments with very low quality/confidence, when considering higher quality evidence only valbenazine or deutetrabenazine are evidence-based first-line treatments for TD, and potentially vitamin E as second-line. Switching to molindone and antipsychotic washout should be avoided. More treatment options and higher-quality trials are needed.

Mimosa pudica L. aqueous extract protects mice against pilocarpine-picrotoxin kindling-induced temporal lobe epilepsy, oxidative stress, and alteration in GABAergic/cholinergic pathways and BDNF expression

Ethnopharmacological studies revealed that the leaves and stems of Mimosa pudica L. (Fabaceae) are widely used for the treatment of epilepsy. This study sought to investigate the effects of the aqueous extract of Mimosa pudica leaves and stems against pilocarpine-picrotoxin kindling-induced temporal lobe epilepsy in mice and its implication on oxidative/nitrosative stress, GABAergic/cholinergic signalling, and brain-derived neurotrophic factor (BDNF) expression. The animals were treated for seven consecutive days as follows: one normal group and one negative control group that received orally distilled water; four test groups that received orally four doses of Mimosa pudica (20, 40, 80, and 160 mg/kg), respectively; and one positive control group that received 300 mg/kg sodium valproate intraperitoneally. One hour after the first treatment (first day), status epilepticus was induced by intraperitoneal injection of a single dose of pilocarpine (360 mg/kg). Then, 23 hours after the injection of pilocarpine to the mice, once again, they received their different treatments. Sixty minutes later, they were injected with a sub-convulsive dose of picrotoxin (1 mg/kg), and the anticonvulsant property of the extract was determined. On day 7, open-field, rotarod, and catalepsy tests were performed. Finally, the mice were sacrificed, and the hippocampi were isolated to quantify some biochemical markers of oxidative/nitrosative stress, GABAergic/cholinergic signalling, and BDNF levels in the hippocampus. Mimosa pudica extracts (160 mg/kg) significantly increased the latency time to status epilepticus by 70.91%. It significantly decreased the number of clonic and tonic seizures to 9.33 ± 1.03 and 5.00 ± 0.89, and their duration to 11.50 ± 2.07 and 6.83 ± 0.75 s, respectively. Exploratory behaviour, motor coordination, and catalepsy were significantly ameliorated, respectively, in the open-field, rotarod, and catalepsy tests. Pilocarpine-picrotoxin-induced alteration of oxidant-antioxidant balance, GABA-transaminase stability, acetylcholinesterase/butyrylcholinesterase activity, and neurogenesis were attenuated by the extract (80-160 mg/kg). This study showed that the aqueous extract of Mimosa pudica leaves and stems ameliorated epileptogenesis of temporal lobe epilepsy and could be used for the treatment of temporal lobe epilepsy.

Therapeutic Effect of Levetiracetam Against Thioacetamide-Induced Hepatic Encephalopathy Through Inhibition of Oxidative Stress and Downregulation of NF-κB, NLRP3, iNOS/NO, Pro-Inflammatory Cytokines and Apoptosis

Hepatic encephalopathy (HE) is a serious brain disorder which associated with neurological and psychiatric manifestations. Oxidative stress and neuroinflammation and apoptosis play main roles in the development of brain damage in HE. Levetiracetam is an antiseizure drug with established antioxidant and anti-inflammatory activities. In the present study we investigated the therapeutic effects of levetiracetam against brain injury in HE and its underlying mechanisms of action. Male C57BL/6 mice were subjected to the induction of HE by the injection of thioacetamide (200 mg/kg) for 2 days. Mice were treated with levetiracetam at two doses (50 or 100 mg/kg/day) for 3 days in the treatment groups. Animals were subjected to a behavioral test and the brain tissues were dissected for histopathological, biochemical, gene expression and immunofluorescence analysis. The results showed that levetiracetam alleviated body weight loss and improved locomotor activity of mice with HE. Levetiracetam treatment decreased the histopathological changes, lipid peroxidation and protein carbonylation while restored the antioxidants (GSH, SOD and CAT) in the brain. Levetiracetam decreased the expression and activity of NF-κB, NOD-like receptor pyrin domain-containing protein 3 (NLRP3) and pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, and IFN-γ) in the brain tissue. Administration of levetiracetam inhibited iNOS/NO pathway and myeloperoxidase (MPO) activity in the brain. Moreover, caspase-3 was decreased and the ratio of Bcl2/Bax was increased in the brain of mice treated with levetiracetam. These findings suggest that levetiracetam may be a promising therapeutic agent for brain injury in HE through inhibiting the oxidative, inflammatory and apoptotic pathways.

10-Gingerol Increases Antioxidant Enzymes and Attenuates Lipopolysaccharide-Induced Inflammation by Modulating Adipokines in 3T3-L1 Adipocytes

BACKGROUND

Obesity increases reactive oxygen species production and alters adipokines levels, resulting in a low-grade chronic inflammation state, which contributes to tissue metabolic dysfunction. 10-gingerol, a phenol present in ginger, has shown potential anti-obesogenic effects in vitro. However, the antioxidant and anti-inflammatory properties of 10-gingerol have not been approached. The aim of this study was to investigate the effects of 10-gingerol on antioxidant enzymes' expression and adipokine production in 3T3-L1 adipocytes in response to lipopolysaccharide (LPS)-induced inflammation.

METHODS

10-gingerol antioxidant capacity was assessed through Oxygen Radical Absorbance Capacity (ORAC) , Ferric Reducing Antioxidant Power (FRAP), and radical scavenging activity of 2,2-diphenyl-2-picrylhydrazyl (DPPH) assays. 3T3-L1 cells were differentiated and stimulated with 100 ng/mL LPSs. Then, 15 µg/mL 10-gingerol was added for 48 h. The mRNA expression and protein abundance of antioxidant enzymes were evaluated by qPCR and Western blot, respectively. Adipokine levels were determined by ELISA.

RESULTS

10-gingerol showed low FRAP and DPPH values but a moderate ORAC value. Moreover, 10-gingerol increased Gpx1 and Sod1 but downregulated Cat expression. Additionally, 10-gingerol significantly increased CAT and GPx1 levels but not SOD-1. Finally, adiponectin and leptin concentrations were increased while resistin and tumor necrosis factor alpha (TNFα) were decreased by 10-gingerol.

CONCLUSIONS

10-gingerol presented antioxidant potential by increasing antioxidant enzymes and attenuated LPS-induced inflammation by modulating adipokines in 3T3-L1 adipocytes.

Effect of Levetiracetam on Oxidant-Antioxidant Activity during Long-Term Temporal Lobe Epilepsy in Rats

Epilepsy is a disorder characterized by a predisposition to generate seizures. Levetiracetam (LEV) is an antiseizure drug that has demonstrated oxidant-antioxidant effects during the early stages of epilepsy in several animal models. However, the effect of LEV on oxidant-antioxidant activity during long-term epilepsy has not been studied. Therefore, the objective of the present study was to determine the effects of LEV on the concentrations of five antioxidant enzymes and on the levels of four oxidant stress markers in the hippocampus of rats with temporal lobe epilepsy at 5.7 months after status epilepticus (SE). The results revealed that superoxide dismutase (SOD) activity was significantly greater in the epileptic group (EPI) than in the control (CTRL), CTRL + LEV and EPI + LEV groups. No significant differences were found among the groups' oxidant markers. However, the ratios of SOD/hydrogen peroxide (H2O2), SOD/glutathione peroxidase (GPx) and SOD/GPx + catalase (CAT) were greater in the EPI group than in the CTRL and EPI + LEV groups. Additionally, there was a positive correlation between SOD activity and GPx activity in the EPI + LEV group. LEV-mediated modulation of the antioxidant system appears to be time dependent; at 5.7 months after SE, the role of LEV may be as a stabilizer of the redox state.