The genetic link between systemic autoimmune disorders and temporal lobe epilepsy: A bioinformatics study

OBJECTIVE

We aimed to explore the underlying pathomechanisms of the comorbidity between three common systemic autoimmune disorders (SADs) [i.e., insulin-dependent diabetes mellitus (IDDM), systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA)] and temporal lobe epilepsy (TLE), using bioinformatics tools. We hypothesized that there are shared genetic variations among these four conditions.

METHODS

Different databases (DisGeNET, Harmonizome, and Enrichr) were searched to find TLE-associated genes with variants; their single nucleotide polymorphisms (SNPs) were gathered from the literature. We also did a separate literature search using PubMed with the following keywords for original articles: "TLE" or "Temporal lobe epilepsy" AND "genetic variation," "single nucleotide polymorphism," "SNP," or "genetic polymorphism." In the next step, the SNPs associated with TLE were searched in the LitVar database to find the shared gene variations with RA, SLE, and IDDM.

RESULTS

Ninety unique SNPs were identified to be associated with TLE. LitVar search identified two SNPs that were shared between TLE and all three SADs (i.e., IDDM, SLE, and RA). The first SNP was rs16944 on the Interleukin-1β (IL-1β) gene. The second genetic variation was ε4 variation of apolipoprotein E (APOE) gene.

SIGNIFICANCE

The shared genetic variations (i.e., rs16944 on the IL-1β gene and ε4 variation of the APOE gene) may explain the underlying pathomechanisms of the comorbidity between three common SADs (i.e., IDDM, SLE, and RA) and TLE. Exploring such shared genetic variations may help find targeted therapies for patients with TLE, especially those with drug-resistant seizures who also have comorbid SADs.

Exploring the Semantic Structure of WMS-IV Verbal Paired Associates using the Hub-and-Spoke Model

OBJECTIVES

This study aimed to identify a well-fitting and theoretically justified item-level latent factor structure for the Wechsler Memory Scales (WMS)-IV verbal paired associates (VerbalPA) subtest to facilitate the ease and accuracy of score interpretations for patients with lateralized temporal lobe epilepsy (TLE).

METHODS

Archival data were used from 250 heterogeneous neurosciences patients who were administered the WMS-IV as part of a standard neuropsychological assessment. Three theoretically motivated models for the latent structure of VerbalPA were tested using confirmatory factor analysis. The first model, based on cognitive principles of semantic processing from hub-and-spoke theory, tested whether performance is related to specific semantic features of target words. The second, motivated by the Cattell-Horn-Carroll (CHC) model of cognitive abilities, investigated whether the associative properties of items influence performance. A third, Hybrid model tested whether performance is related to both semantic and associative properties of items. The best-fitting model was tested for diagnostic group effects contrasting the heterogeneous neuroscience patients with subsets of left and right TLE (n = 51, n = 26, respectively) patients.

RESULTS

The Hybrid model was found to have the best fit. Patients with left TLE scored significantly less well than the heterogeneous neurosciences sample on selected semantic factor scores, although the effect size was small.

CONCLUSIONS

Future editions of the WMS may consider implementing a semantic scoring structure for the VerbalPA to facilitate test score interpretation. Additionally, these results suggest that principles of hub-and-spoke theory may be integrated into CHC cognitive ability taxonomy.

An aqueous extract of Lantana camara attenuates seizures, memory impairment, and anxiety in kainate-treated mice: Evidence of GABA level, oxidative stress, immune and neuronal loss modulation

BACKGROUND

Epilepsy is a neurological disorder characterized by spontaneous recurrent seizures. Lantana camara (Verbenaceae) is a plant used in Cameroonian traditional medicine to treat dementia, epilepsy, and sleeping disorders. Hence, this study aimed to assess the antiepileptic-like effects of an aqueous extract of L. camara leaves on seizures induced by kainate in mice, and possible mechanisms of action.

METHODS

Mice were divided into two groups: a normal control group treated with 0.9% saline (10 ml/kg, i.p.), and a kainate group treated with kainate (10 mg/kg, i.p.). All mice that developed status epilepticus were individually observed for spontaneous seizures. Eighteen days after the induction of status epilepticus, mice that exhibited spontaneous seizures were further divided into 6 groups of 7 mice each and treated as follows: a kainate group treated with 0.9% saline (10 ml/kg, p.o.), two positive control groups either treated with sodium valproate (300 mg/kg, p.o.) or with piracetam (200 mg/kg, p.o.), and three test groups received the extract (230, 460, and 917 mg/kg, p.o.). The control group was treated with 0.9% saline (10 ml/kg, p.o.). These treatments lasted 14 days and the animals were observed 6 h per day for behavioral seizures. Subsequently, the animals were evaluated for anxiety disorders and memory impairment. Animals were then sacrificed and the hippocampus or prefrontal cortex was collected for histological and biochemical analyses. Furthermore, the dilacerates of the hippocampi were stored for white blood cell count.

RESULTS

The aqueous extract of L. camara (460 mg/kg) remarkably decreased (p < 0.001) the number and duration of seizures compared to sodium valproate. Also, it significantly increased the level of GABA both in the hippocampus and prefrontal cortex and protected these organs from oxidative stress. Furthermore, the extract (230 mg/kg) induced the highest reduction in the number of white blood cells in the hippocampus. Finally, the extract (917 mg/kg) significantly attenuated neuronal loss in the CA1, CA2, and CA3 regions of the hippocampus. All these compared to the negative control.

CONCLUSION

These results suggest that the aqueous extract of L. camara has an antiepileptic-like effect comparable to that of sodium valproate. This, therefore, warrants further investigation into the effect of bioactive molecules present in the extract using in vitro and in vivo models of epilepsy.

Anti-high mobility group box protein 1 monoclonal antibody downregulating P-glycoprotein as novel epilepsy therapeutics

Epilepsy, a neurological illness, is characterized by recurrent uncontrolled seizures. There are many treatments of options that can be used as the therapy of epilepsy. However, anti-seizure medications as the primary treatment choice for epilepsy show many possible adverse effects and even pharmacoresistance to the therapy. High Mobility Group Box 1 (HMGB1) as an initiator and amplifier of the neuroinflammation is responsible for the onset and progression of epilepsy by overexpressing P-glycoprotein on the blood brain barrier. HMGB1 proteins then activate TLR4 in neurons and astrocytes, in which proinflammatory cytokines are produced. Anti-HMGB1 mAb works by blocking the HMGB1, reducing inflammatory activity in the brain that may affect epileptogenesis. Through the process, anti-HMGB1 mAb reduces the TLR4 activity and other receptors that may involve in promote signal of epilepsy such as RAGE. Several studies have shown that anti-HMGB1 has the potential to inhibit the increase in serum HMGB1 in plasma and brain tissue. Further research is needed to identify the mechanism of the inhibiting of overexpression of P-glycoprotein through anti-HMGB1 mAb.