Adie's tonic pupil after COVID-19: a case report and literature review.

Objective: Various neurological complications have been reported after COVID-19. The study aimed to document an unusual case of Adie's tonic pupil following COVID-19. Methods: The study was a case report. Results: A 28-year-old female had suffered a flu-like disease about 2 months before and the SARSCoV-2 polymerase chain reaction test at that time was positive. Two weeks after infection she noticed an asymmetry between the pupils. The only pathological finding on examination was anisocoria with a larger left pupil in ambient light. Light reflexes were observed in the right eye, while in the left eye, they were absent. Also, there was no near response in the left pupil. A 0.1% pilocarpine test results validated Adie's pupil diagnosis. After one year of follow-up, the anisocoria decreased but did not completely recover. Discussion: COVID-19 may cause damage to neural structures due to autoimmune ways by activating immune pathways or because of vascular complications that may affect the vasa nervorum. Adie's tonic pupil is often idiopathic, but it may develop following viral infection. Conclusions: Ocular complications that involve pupil abnormalities may manifest following COVID-19. In the cases of Adie's tonic pupil, infectious diseases, including COVID-19, should be questioned. Abbreviations: RT PCR = reverse transcription polymerase chain reaction.

Intracellular Signaling Pathways Involved in the Regulation of Gene Expression by Pilocarpine.

OBJECTIVES: Pilocarpine is commonly used clinically to treat dry mouth. The long-term administration of pilocarpine reportedly improves salivary secretion more effectively than short-term administration. Therefore, we hypothesized that pilocarpine alters gene expression in salivary glands via muscarinic receptor stimulation. This study aimed to investigate the effects of pilocarpine use on gene expression mediated by mitogen-activated protein kinase (MAPK) activity. METHODS: The effects of pilocarpine on gene expression were investigated in rats and human salivary gland (HSY) cells using several inhibitors of intracellular signaling pathways. Gene expression in the rat submandibular gland and HSY cells was determined using reverse transcription-quantitative polymerase chain reaction analysis of total RNA. RESULTS: In animal experiments, at 7 days after pilocarpine stimulation, Ctgf and Sgk1 expressions were increased in the submandibular gland. In cell culture experiments, pilocarpine increased Ctgf expression in HSY cells. The mitogen-activated protein kinase kinase inhibitor trametinib, the Src inhibitor PP2, and the muscarinic acetylcholine receptor antagonist atropine suppressed the effect of pilocarpine on gene expression. CONCLUSIONS: Pilocarpine enhances Ctgf and Sgk1 expressions by activating Src-mediated MAPK activity. Although further studies are required to fully understand the roles of Ctgf and Sgk1, changes in gene expression may play an important role in improving salivary secretions.

Cholinergic and behavior-dependent beta and gamma waves are coupled between olfactory bulb and hippocampus.

Olfactory oscillations may enhance cognitive processing through coupling with beta (ß, 15-30 Hz) and gamma (γ, 30-160 Hz) activity in the hippocampus (HPC). We hypothesize that coupling between olfactory bulb (OB) and HPC oscillations is increased by cholinergic activation in control rats and is reduced in kainic-acid-treated epileptic rats, a model of temporal lobe epilepsy. OB γ2 (63-100 Hz) power was higher during walking and immobility-awake (IMM) compared to sleep, while γ1 (30-57 Hz) power was higher during grooming than other behavioral states. Muscarinic cholinergic agonist pilocarpine (25 mg/kg ip) with peripheral muscarinic blockade increased OB power and OB-HPC coherence at ß and γ1 frequency bands. A similar effect was found after physostigmine (0.5 mg/kg ip) but not scopolamine (10 mg/kg ip). Pilocarpine increased bicoherence and cross-frequency coherence (CFC) between OB slow waves (SW, 1-5 Hz) and hippocampal ß, γ1 and γ2 waves, with stronger coherence at CA1 alveus and CA3c than CA1 stratum radiatum. Bicoherence further revealed a nonlinear interaction of ß waves in OB with ß waves at the CA1-alveus. Beta and γ1 waves in OB or HPC were segregated at one phase of the OB-SW, opposite to the phase of γ2 and γ3 (100-160 Hz) waves, suggesting independent temporal processing of ß/γ1 versus γ2/γ3 waves. At CA1 radiatum, kainic-acid-treated epileptic rats compared to control rats showed decreased theta power, theta-ß and theta-γ2 CFC during baseline walking, decreased CFC of HPC SW with γ2 and γ3 waves during baseline IMM, and decreased coupling of OB SW with ß and γ2 waves at CA1 alveus after pilocarpine. It is concluded that ß and γ waves in the OB and HPC are modulated by a slow respiratory rhythm, in a cholinergic and behavior-dependent manner, and OB-HPC functional connectivity at ß and γ frequencies may enhance cognitive functions.

Neuroprotective potential of topiramate, pregabalin and lacosamide combination in a rat model of acute SE and intractable epilepsy: Perspectives from electroencephalographic, neurobehavioral and regional degenerative analysis.

The lithium-pilocarpine model is commonly used to recapitulate characteristics of human intractable focal epilepsy. In the current study, we explored the impact of topiramate (TPM) alone and in combination with pregabalin and lacosamide administration for 6 weeks on the evolution of spontaneous recurrent seizures (SRS) and disease-modifying potential on associated neuropsychiatric comorbidities. In addition, redox impairments and neurodegeneration in hippocampus regions vulnerable to temporal lobe epilepsy (TLE) were assessed by cresyl violet staining. Results revealed that acute electrophysiological (EEG) profiling of the ASD cocktail markedly halted sharp ictogenic spikes as well as altered dynamics of brain wave oscillations thus validating the need for polytherapy vs. monotherapy. In TLE animals, pharmacological intervention for 6 weeks with topiramate 10 mg/kg in combination with PREG and LAC at the dose of 20 mg/kg exhibited marked protection from SRS incidence, improved body weight, offensive aggression, anxiety-like behavior, cognitive impairments, and depressive-like behavior (p < 0.05). Moreover, combination therapy impeded redox impairments as evidenced by decreased MDA and AchE levels and increased activity of antioxidant SOD, GSH enzymes. Furthermore, polytherapy rescued animals from SE-induced neurodegeneration with increased neuronal density in CA1, CA3c, CA3ab, hilus, and granular cell layer (GCL) of the dentate gyrus. In conclusion, early polytherapy with topiramate in combination with pregabalin and lacosamide prompted synergy and prevented epileptogenesis with associated psychological and neuropathologic alterations.

Gut microbiota and serum metabolomic alterations in modulating the impact of fecal microbiota transplantation on ciprofloxacin-induced seizure susceptibility.

Introduction: The gut microbiota and the microbiota-gut-brain axis have gained considerable attention in recent years, emerging as key players in the mechanisms that mediate the occurrence and progression of many central nervous system-related diseases, including epilepsy. In clinical practice, one of the side effects of quinolone antibiotics is a lower seizure threshold or aggravation. However, the underlying mechanism remains unclear. Methods: We aimed to unravel the intrinsic mechanisms through 16S rRNA sequencing and serum untargeted metabolomic analysis to shed light on the effects of gut microbiota in ciprofloxacin-induced seizure susceptibility and lithium pilocarpine-induced epilepsy rat models. Results: We observed that ciprofloxacin treatment increased seizure susceptibility and caused gut dysbiosis. We also found similar changes in the gut microbiota of rats with lithium pilocarpine-induced epilepsy. Notably, the levels of Akkermansia and Bacteroides significantly increased in both the ciprofloxacin-induced seizure susceptibility and lithium pilocarpine-induced epilepsy rat models. However, Marvinbryantia, Oscillibacter, and Ruminococcaceae_NK4A214_group showed a coincidental reduction. Additionally, the serum untargeted metabolomic analysis revealed decreased levels of indole-3-propionic acid, a product of tryptophan-indole metabolism, after ciprofloxacin treatment, similar to those in the plasma of lithium pilocarpine-induced epilepsy in rats. Importantly, alterations in the gut microbiota, seizure susceptibility, and indole-3-propionic acid levels can be restored by fecal microbiota transplantation. Conclusion: In summary, our findings provide evidence that ciprofloxacin-induced seizure susceptibility is partially mediated by the gut microbiota and tryptophan-indole metabolism. These associations may play a role in epileptogenesis, and impacting the development progression and treatment outcomes of epilepsy.

Electroencephalographic and Behavioral Effects of Intranasal Administration of a Na+, K+-ATPase-Activating Antibody after Status Epilepticus.

Status epilepticus (SE) is a medical emergency associated with high mortality and morbidity. Na+, K+-ATPase, is a promising therapeutic target for SE, given its critical role in regulation of neuron excitability and cellular homeostasis. We investigated the effects of a Na+, K+-ATPase-activating antibody (DRRSAb) on short-term electrophysiological and behavioral consequences of pilocarpine-induced SE. Rats were submitted to pilocarpine-induced SE, followed by intranasal administration (2 µg/nostril). The antibody increased EEG activity following SE, namely, EEG power in theta, beta, and gamma frequency bands, assessed by quantitative analysis of EEG power spectra. One week later, DRRSAb-treated animals displayed less behavioral hyperreactivity in pick-up tests and better performance in novel object recognition tests, indicating that the intranasal administration of this Na+, K+-ATPase activator immediately after SE improves behavioral outcomes at a later time point. These results suggest that Na+, K+-ATPase activation warrants further investigation as an adjunctive therapeutic strategy for SE.

Cognitive comorbidities in the rat pilocarpine model of epilepsy.

Patients with epilepsy are prone to cognitive decline, depression, anxiety and other behavioral disorders. Cognitive comorbidities are particularly common and well-characterized in people with temporal lobe epilepsy, while inconsistently addressed in epileptic animals. Therefore, the aim of this study was to ascertain whether there is good evidence of cognitive comorbidities in animal models of epilepsy, in particular in the rat pilocarpine model of temporal lobe epilepsy. We searched the literature published between 1990 and 2023. The association of spontaneous recurrent seizures induced by pilocarpine with cognitive alterations has been evaluated by using various tests: contextual fear conditioning (CFC), novel object recognition (NOR), radial and T-maze, Morris water maze (MWM) and their variants. Combination of results was difficult because of differences in methodological standards, in number of animals employed, and in outcome measures. Taken together, however, the analysis confirmed that pilocarpine-induced epilepsy has an effect on cognition in rats, and supports the notion that this is a valid model for assessment of cognitive temporal lobe epilepsy comorbidities in preclinical research.

Effect of quercetin against pilocarpine-induced epilepsy in mice.

Globally, an estimated 50 million people are affected by epilepsy, a persistent, noncommunicable neurological ailment. Quercetin (QR) is a prevalent flavonoid substance extensively dispersed throughout agricultural life. In a pilocarpine (PILO)-induced epilepsy model in mice, this investigation aimed to determine whether QR has an antiepileptic effect and explore its putative mechanism of action. Fifty mice were allocated into seven groups, with six in every group. The first group received physiological saline, the second group was given diazepam (1 mg/kg), and four groups were administered QR at 50, 100, 150, and 200 mg/kg, respectively. The seventh group (the induction group) received normal saline. After 30 min, all groups were injected intraperitoneally with PILO. The impact of QR on motor coordination was assessed using the rotarod test, while measures such as latency to first seizure, generalized tonic-clonic seizures (GTCS), number of convulsions, and mortality were recorded. Serum samples were collected through the retro-orbital route to measure prostaglandin E2 (PGE2) and interleukin 1 beta (IL-1ß) levels. QR showed no significant difference in motor impairment, but increased duration until the initial seizure occurred and declined the mortality rate, duration of GTCS, and incidence of convulsions. All doses of QR significantly reduced PGE2 levels (P ≤ 0.05). However, QR's effect on IL-1ß reduction was statistically insignificant (P > 0.05). QR's capacity to inhibit PILO-induced epilepsy by decreasing IL-1 and PGE2 levels is supported by this study. The results of this work indicate that QR could have a function to treat acute epilepsy.

Physiologically Based Pharmacokinetic Modeling and Clinical Extrapolation for Topical Application of Pilocarpine on Eyelids: A Comprehensive Study.

Exploiting a convenient and highly bioavailable ocular drug delivery approach is currently one of the hotspots in the pharmaceutical industry. Eyelid topical application is seen to be a valuable strategy in the treatment of chronic ocular diseases. To further elucidate the feasibility of eyelid topical administration as an alternative route for ocular drug delivery, pharmacokinetic and pharmacodynamic studies of pilocarpine were conducted in rabbits. Besides, a novel physiologically based pharmacokinetic (PBPK) model describing eyelid transdermal absorption and ocular disposition was developed in rabbits. The PBPK model of rabbits was extrapolated to human by integrating the drug-specific permeability parameters and human physiological parameters to predict ocular pharmacokinetic in human. After eyelid topical application of pilocarpine, the concentration of pilocarpine in iris peaked at 2 h with the value of 18,724 ng/g and the concentration in aqueous humor peaked at 1 h with the value of 1,363 ng/mL. Significant miotic effect were observed from 0.5 h to 4.5 h after eyelid topical application of pilocarpine in rabbits, while that were observed from 0.5 h to 3.5 h after eyedrop instillation. The proposed eyelid PBPK model was capable of reasonably predicting ocular exposure of pilocarpine after application on the eyelid skin and based on the PBPK model, the human ocular concentration was predicted to be 10-fold lower than that in rabbits. And it was suggested that drugs applied on the eyelid skin could transfer into the eyeball through corneal pathway and scleral pathway. This work could provide pharmacokinetic and pharmacodynamic data for the development of eyelid drug delivery, as well as the reference for clinical applications.

Mammalian models of status epilepticus - Their value and limitations.

Status epilepticus (SE) is a medical and neurologic emergency that may lead to permanent brain damage, morbidity, or death. Animal models of SE are particularly important to study the pathophysiology of SE and mechanisms of SE resistance to antiseizure medications with the aim to develop new, more effective treatments. In addition to rodents (rats or mice), larger mammalian species such as dogs, pigs, and nonhuman primates are used. This short review describes and discusses the value and limitations of the most frequently used mammalian models of SE. Issues that are discussed include (1) differences between chemical and electrical SE models; (2) the role of genetic background and environment on SE in rodents; (3) the use of rodent models (a) to study the pathophysiology of SE and mechanisms of SE resistance; (b) to study developmental aspects of SE; (c) to study the efficacy of new treatments, including drug combinations, for refractory SE; (d) to study the long-term consequences of SE and identify biomarkers; (e) to develop treatments that prevent or modify epilepsy; (e) to study the pharmacology of spontaneous seizures; (4) the limitations of animal models of induced SE; and (5) the advantages (and limitations) of naturally (spontaneously) occurring SE in epileptic dogs and nonhuman primates. Overall, mammalian models of SE have significantly increased our understanding of the pathophysiology and drug resistance of SE and identified potential targets for new, more effective treatments. This paper was presented at the 9th London-Innsbruck Colloquium on Status Epilepticus and Acute Seizures held in April 2024.

Molecular Genetics of Acquired Temporal Lobe Epilepsy.

An epilepsy diagnosis reduces a patient's quality of life tremendously, and it is a fate shared by over 50 million people worldwide. Temporal lobe epilepsy (TLE) is largely considered a nongenetic or acquired form of epilepsy that develops in consequence of neuronal trauma by injury, malformations, inflammation, or a prolonged (febrile) seizure. Although extensive research has been conducted to understand the process of epileptogenesis, a therapeutic approach to stop its manifestation or to reliably cure the disease has yet to be developed. In this review, we briefly summarize the current literature predominately based on data from excitotoxic rodent models on the cellular events proposed to drive epileptogenesis and thoroughly discuss the major molecular pathways involved, with a focus on neurogenesis-related processes and transcription factors. Furthermore, recent investigations emphasized the role of the genetic background for the acquisition of epilepsy, including variants of neurodevelopmental genes. Mutations in associated transcription factors may have the potential to innately increase the vulnerability of the hippocampus to develop epilepsy following an injury-an emerging perspective on the epileptogenic process in acquired forms of epilepsy.

Rat strain differences in seizure frequency and hilar neuron loss after systemic treatment with pilocarpine.

At least 3 months after systemic treatment with pilocarpine to induce status epilepticus, Long-Evans and Sprague-Dawley rats were video-EEG monitored for seizures continuously for 1 month. Rats were then perfused, hippocampi were processed for Nissl staining, and hilar neurons were quantified. Seizure frequency in Long-Evans rats was 1/10th of that in Sprague-Dawley rats, and more variable. Hilar neuron loss was also less severe in Long-Evans rats. However, there was no correlation between hilar neuron loss and seizure frequency in either strain. The low and variable seizure frequency suggests limited usefulness of pilocarpine-treated Long-Evans rats for some epilepsy experiments.

The latency to awake from induced-obstructive sleep apnea is reduced in rats with chronic epilepsy.

OSA is known to increase the risk for SUDEP in persons with epilepsy, but the relationship between these two factors is not clear. Also, there is no study showing the acute responses to obstructive apnea in a chronic epilepsy model. Therefore, this study aimed to characterize cardiorespiratory responses to obstructive apnea and chemoreceptor stimulation in rats. In addition, we analyzed respiratory centers in the brain stem by immunohistochemistry. Epilepsy was induced with pilocarpine. About 30-60 days after the first spontaneous seizure, tracheal and thoracic balloons, and electrodes for recording the electroencephalogram, electromyogram, and electrocardiogram were implanted. Intermittent apneas were made by inflation of the tracheal balloon during wakefulness, NREM sleep, and REM sleep. During apnea, respiratory effort increased, and heart rate fell, especially with apneas made during wakefulness, both in control rats and rats with epilepsy. Latency to awake from apnea was longer with apneas made during REM than NREM, but rats with epilepsy awoke more rapidly than controls with apneas made during REM sleep. Rats with epilepsy also had less REM sleep. Cardiorespiratory responses to stimulation of carotid chemoreceptors with cyanide were similar in rats with epilepsy and controls. Immunohistochemical analysis of Phox2b, tryptophan hydroxylase, and NK1 in brain stem nuclei involved in breathing and sleep (retrotrapezoid nucleus, pre-Bötzinger complex, Bötzinger complex, and caudal raphe nuclei) revealed no differences between control rats and rats with epilepsy. In conclusion, our study showed that rats with epilepsy had a decrease in the latency to awaken from apneas during REM sleep, which may be related to neuroplasticity in some other brain regions related to respiratory control, awakening mechanisms, and autonomic modulation.

Ketogenic Diets Alter the Gut Microbiome, Resulting in Decreased Susceptibility to and Cognitive Impairment in Rats with Pilocarpine-Induced Status Epilepticus.

A ketogenic diet (KD) is a high-fat, low-carbohydrate, and low-protein diet that exerts antiepileptic effects by attenuating spontaneous recurrent seizures, ameliorating learning and memory impairments, and modulating the gut microbiota composition. However, the role of the gut microbiome in the antiepileptic effects of a KD on temporal lobe epilepsy (TLE) induced by lithium-pilocarpine in adult rats is still unknown. Our study provides evidence demonstrating that a KD effectively mitigates seizure behavior and reduces acute-phase epileptic brain activity and that KD treatment alleviates hippocampal neuronal damage and improves cognitive impairment induced by TLE. We also observed that the beneficial effects of a KD are compromised when the gut microbiota is disrupted through antibiotic administration. Analysis of gut microbiota components via 16S rRNA gene sequencing in fecal samples collected from TLE rats fed either a KD or a normal diet. The Chao1 and ACE indices showed decreased species variety in KD-fed rats compared to TLE rats fed a normal diet. A KD increased the levels of Actinobacteriota, Verrucomicrobiota and Proteobacteria and decreased the level of Bacteroidetes. Interestingly, the abundances of Actinobacteriota and Verrucomicrobiota were positively correlated with learning and memory ability, and the abundance of Proteobacteria was positively correlated with seizure susceptibility. In conclusion, our study revealed the significant antiepileptic and neuroprotective effects of a KD on pilocarpine-induced epilepsy in rats, primarily mediated through the modulation of the gut microbiota. However, whether the gut microbiota mediates the antiseizure effects of a KD still needs to be better elucidated.

Crack cocaine inhalation increases seizure susceptibility by reducing acetylcholinesterase activity.

Crack cocaine is a highly addictive and potent stimulant drug. Animal studies have shown that the cholinergic system plays a role in neurotoxicity induced by cocaine or its active metabolites inhalation. Behavioral alterations associated with crack cocaine use include hyperactivity, depressed mood, and decreased seizure threshold. Here we evaluate the acetylcholinesterase (AChE) and reactive oxygen species (ROS) activity, behavioral profile, and the threshold for epileptic seizures in rats that received intrahippocampal pilocarpine (H-PILO) followed by exposure to crack cocaine (H-PILO + CRACK). Animals exposed to H-PILO + CRACK demonstrated increased severity and frequency of limbic seizures. The AChE activity was reduced in the groups exposed to crack cocaine alone (CRACK) and H-PILO + CRACK, whereas levels of ROS remained unchanged. In addition, crack cocaine exposure increased vertical locomotor activity, without changing water and sucrose intake. Short-term memory consolidation remained unchanged after H-PILO, H-PILO + CRACK, and CRACK administration. Overall, our data suggest that crack cocaine inhalation reduced the threshold for epileptic seizures in rats submitted to low doses of pilocarpine through the inhibition of AChE. Taken together, our findings can be useful in the development of effective strategies for preventing and treating the harmful effects of cocaine and crack cocaine on the central nervous system.

Glycoprotein Non-metastatic Melanoma Protein B (GPNMB) Protects Against Neuroinflammation and Neuronal Loss in Pilocarpine-induced Epilepsy via the Regulation of Microglial Polarization.

Epilepsy is a progressive neurodegenerative disease highlighted by recurrent seizures, neuroinflammation, and the loss of neurons. Microglial dysfunction is commonly found in epileptic foci and contributes to neuroinflammation in the initiation and progression of epilepsy. Glycoprotein non-metastatic melanoma protein B (GPNMB), a transmembrane glycoprotein, has been involved in the microglial activation and neuroinflammation response. The present study investigated the functional significance of GPNMB in epilepsy. A proven model of epilepsy was established by intraperitoneal injection of pilocarpine to male Sprague Dawley rats. Lentivirus vectors carrying GPNMB or GPNMB short hairpin RNA (shGPNMB) were injected into the hippocampus to induce overexpression or knockdown of GPNMB. GPNMB expression was significantly upregulated and overexpression of GPNMB in the hippocampus reduced seizure activity and neuronal loss after status epilepticus (SE). We here focused on the effects of GPNMB deficiency on neuronal injury and microglia polarization 28 days after SE. GPNMB knockdown accelerated neuronal damage in the hippocampus, evidenced by increased neuron loss and neuronal cell apoptosis. Following GPNMB knockdown, M1 polarization (iNOS) and secretion of pro-inflammatory cytokines IL-6, IL-1ß, and TNF-α were increased, and M2 polarization (Arg1) and secretion of anti-inflammatory cytokines IL-4, IL-10, and TGF-ß were decreased. BV2 cells were used to further confirm the regulatory role of GPNMB in modulating phenotypic transformations and inflammatory cytokine expressions in microglia. In conclusion, these results indicated that GPNMB suppressed epilepsy through repression of hippocampal neuroinflammation, suggesting that GPNMB might be considered the potential neurotherapeutic target for epilepsy management and play a protective role against epilepsy by modulating the polarization of microglia.

As-Needed Pilocarpine for Radiation-Induced Xerostomia in Head and Neck Cancers.

OBJECTIVES: This study aimed to evaluate the efficacy of as-needed pilocarpine for the management of radiation-induced xerostomia. Additionally, the study sought to assess the side effects associated with an as-needed regimen. METHODS: A randomized, double-blinded, placebo-controlled crossover study was conducted on patients who had undergone radiation therapy for head and neck cancers and developed xerostomia. Participants took pilocarpine or placebo as needed for symptom relief at 2 weeks per treatment, which included a one-week washout period. The primary outcome measure was the severity of dry mouth symptoms, quantified using the Xerostomia Inventory (XI). The primary outcome was the change in the XI score. RESULTS: Among the 20 participants who completed the crossover study, there was a significant reduction in XI scores during the treatment phase with pilocarpine compared to the scores during the placebo phase. The mean difference in XI scores was -18.05 (95% CI: -17.17, -6.13, p < 0.001), with a-49.77 ± 3.22% change (p < 0.001). Only one participant withdrew due to pilocarpine side effects. CONCLUSION: As-needed pilocarpine administration is effective in relieving symptoms of radiation-induced xerostomia, with fewer side effects and reduced treatment costs compared to fixed-dose regimens. This study guides the potential shift toward flexible dosing strategies in clinical practice, promoting enhanced patient-centered, tailored care and adherence. LEVEL OF EVIDENCE: Level 2. According to the Oxford Center for Evidence-Based Medicine 2011 level of evidence guidelines Laryngoscope, 2024.

Time- and Region-Specific Selection of Reference Genes in the Rat Brain in the Lithium-Pilocarpine Model of Acquired Temporal Lobe Epilepsy.

Reverse transcription followed by quantitative polymerase chain reaction (RT-qPCR) is a commonly used tool for gene expression analysis. The selection of stably expressed reference genes is required for accurate normalization. The aim of this study was to identify the optimal reference genes for RT-qPCR normalization in various brain regions of rats at different stages of the lithium-pilocarpine model of acquired epilepsy. We tested the expression stability of nine housekeeping genes commonly used as reference genes in brain research: Actb, Gapdh, B2m, Rpl13a, Sdha, Ppia, Hprt1, Pgk1, and Ywhaz. Based on four standard algorithms (geNorm, NormFinder, BestKeeper, and comparative delta-Ct), we found that after pilocarpine-induced status epilepticus, the stability of the tested reference genes varied significantly between brain regions and depended on time after epileptogenesis induction (3 and 7 days in the latent phase, and 2 months in the chronic phase of the model). Pgk1 and Ywhaz were the most stable, while Actb, Sdha, and B2m demonstrated the lowest stability in the analyzed brain areas. We revealed time- and region-specific changes in the mRNA expression of the housekeeping genes B2m, Actb, Sdha, Rpl13a, Gapdh, Hprt1, and Sdha. These changes were more pronounced in the hippocampal region during the latent phase of the model and are thought to be related to epileptogenesis. Thus, RT-qPCR analysis of mRNA expression in acquired epilepsy models requires careful selection of reference genes depending on the brain region and time of analysis. For the time course study of epileptogenesis in the rat lithium-pilocarpine model, we recommend the use of the Pgk1 and Ywhaz genes.

A Case Report of Acute Bilateral Mydriasis Induced by Herbal Medication.

Ma Huang (Ephedra), a traditional herbal remedy, which contains pseudoephedrine and ephedrine, has sympathomimetic characteristics. Despite being banned by the Federal Drug Administration in 2004, it is still used for weight loss and energy boosting in some countries. A previous healthy 42-year-old woman experienced sudden blurred vision in both eyes. Her pupils were dilated to 6 mm each, showing diminished light reflex responses, and were not responsive to both 0.1% and 1% pilocarpine. The day before the onset of her symptoms she had taken a herbal supplement. The woman's herbal medicine was believed to contain ephedrine, a component found in Ma Huang. The sympathomimetic effects of this substance could potentially induce mydriasis. After discontinuing the medication, her symptoms improved over 4 days, leading to a suspicion of drug-induced bilateral mydriasis. Herbal products prescribed for weight loss, which may contain potential elements such as Ma Huang, could lead to unforeseen side effects like bilateral mydriasis, and should be appropriately highlighted.

Does lower dose pilocarpine have a role in radiation-induced xerostomia in the modern radiotherapy era? A single-center experience based on patient-reported outcome measures.

PURPOSE: This study aims to investigate the efficacy of lower dose pilocarpine in alleviating late dry mouth symptoms in head and neck cancer patients received radiotherapy. METHODS: Eighteen head and neck cancer patients experiencing persistent dry mouth were enrolled in this study. All participants started pilocarpine treatment a median of 6 months post-radiotherapy. Initially, patients received pilocarpine at 5 mg/day, with a gradual increase to the recommended dose of 15 mg/day. A Patient-Reported Outcome Measurement (PROMs) questionnaire assessed symptoms' severity related to hyposalivation. RESULTS: All patients reported symptomatic dry mouth above grade 2 before starting the medication. Pilocarpine treatment continued based on patients' self-assessment, with a median duration of 12 months (range, 3-36 months). The median daily maintenance dose was 10 mg (range, 5 to 20 mg). Total PROMs scores significantly decreased following medication, from 13 points (range 7-18 points) to 7 points (range 4-13 points) (p = 0.001). Significant improvements were observed in questions related to dry mouth (p < 0.001), water intake during eating (p = 0.01), carrying water (p = 0.01), taste (p < 0.001), and water intake during speech (p < 0.001). Initial and maintenance doses of pilocarpine were lower, and the duration of pilocarpine usage was shorter in patients treated with intensity-modulated radiation therapy compared to conformal radiotherapy (12 months vs. 25 months, p = 0.04). CONCLUSION: Pilocarpine may be considered at doses lower for late-term dry mouth. With modern radiotherapy techniques effectively preserving the parotid gland, short-term use may be recommended in these patients. Future studies may enhance the development of a more robust patient selection criteria model.