Neuroscience, Cellular and Molecular Neuroscience, Pharmacology, Toxicology and Pharmaceutics, Cell Biology
13
Scopus Publications
Scopus Publications
Targeting Hsp90 with cemdomespib reduces seizure burden and alters disease course in preclinical epilepsy models Yara Sheeni, Prince Kumar Singh, Sereen Sandouka, Taige Zhang, Alina Nemirovski, et al. Epilepsia, 2026 Objective Epilepsy is a chronic neurological disorder characterized by recurrent seizures and frequent cognitive and psychiatric comorbidities. Although current antiseizure medications provide symptomatic relief, they fail to prevent or modify epileptogenesis. Heat shock protein 90 (Hsp90) is increasingly recognized as a regulator of neuroinflammatory and oxidative stress pathways implicated in seizure generation and disease progression. Here, we investigated the therapeutic potential of cemdomespib, a novel and selective Hsp90 inhibitor, across complementary preclinical models of epilepsy. Methods In vitro, cemdomespib was evaluated in the low‐magnesium model of epileptiform activity for its effects on neuronal calcium dynamics, mitochondrial membrane stability, and reactive oxygen species (ROS) generation. In vivo, acute seizure protection was assessed in the pentylenetetrazol (PTZ) model, and antiepileptogenic efficacy was tested in the kainic acid‐induced status epilepticus (KA‐SE) model using chronic video‐electrocorticographic recordings. Behavioral outcomes relevant to epilepsy‐associated comorbidities, including anxiety‐like behavior and exploratory activity, were also examined. Results Cemdomespib reduced epileptiform calcium oscillations, stabilized mitochondrial membrane potential, and suppressed ROS generation in vitro. In the PTZ model, 45% of pretreated animals were protected from seizures, and those that seized exhibited reduced severity, shorter duration, and delayed onset. In the KA‐SE model, cemdomespib significantly mitigated the severity of SE and reduced the emergence of spontaneous recurrent seizures during the chronic phase, as evidenced by lower seizure frequency, decreased cumulative seizure burden, and prolonged latency to seizure onset. Furthermore, treated animals demonstrated improved anxiety‐like behavior and enhanced exploratory activity. Significance Cemdomespib confers both acute seizure protection and long‐term suppression of epileptogenesis, likely through Hsp90‐dependent regulation of mitochondrial integrity and redox signaling. These findings highlight Hsp90 inhibition as a promising therapeutic strategy for seizure control while also mitigating the progression of epileptogenesis and its associated neurobehavioral impairments.
Enigmatic intractable Epilepsy patients have antibodies that bind glutamate receptor peptides, kill neurons, damage the brain, and cause Generalized Tonic Clonic Seizures Rhoda Olowe Taiwo, Hadassa Sterm Goldberg, Nili Ilouz, Prince Kumar Singh, Tawfeeq Shekh-Ahmad, et al. Journal of Neural Transmission, 2025 Epilepsy affects 1–2% of the world population, is enigmatic in 30% of cases, and is often intractable, unresponsive to antiepileptic drugs, and accompanied by cognitive, psychiatric and behavioral problems. Tests for Autoimmune Epilepsy are not performed routinely, and limited to passive diagnosis of known autoimmune antibodies, without essential functional tests to reveal active pathogenic antibodies. We investigated two young Epilepsy patients with different Epilepsy characteristics, repeated intractable seizures, and enigmatic etiology. We suspected Autoimmune Epilepsy. We found that both patients have elevated IgG antibodies, and three types of glutamate receptor antibodies, to: AMPA-GluR3B, NMDA-NR1 and NMDA-NR2 peptides. In contrast, they lack autoantibodies to: LGI1, CASPR2, GABA-RB1, Amphiphysin, CV2, PNMA1, Ri, Yo, Hu, Recoverin, Soxi and Titin. IgG antibodies of both patients bound and killed human neural cells In vitro. Moreover, In vivo video EEG studies in naive rats revealed that patient’s IgG antibodies, infused continually into rat brain, bound neural cells in the hippocampus and cortex, caused neural loss in these brain regions, and induced recurrent Generalized Tonic Clonic Seizures. We assume they can do so also in the patient’s brain. This is the first model of human Autoimmune Epilepsy in rats. It can serve for discovery of patient’s pathogenic antibodies, and drug development. Tests for autoimmune antibodies that bind glutamate receptor peptides, and functional diagnostic tests, are obligatory in all enigmatic intractable Epilepsy patients. Current diagnosis of Autoimmune Epilepsy is insufficient! If pathogenic antibodies are found, intractable patients must receive available, suitable and potentially life-changing immunotherapies for Autoimmune Epilepsy.
Nrf2 is predominantly expressed in hippocampal neurons in a rat model of temporal lobe epilepsy Sereen Sandouka, Aseel Saadi, Prince Kumar Singh, Rhoda Olowe, Tawfeeq Shekh-Ahmad Cell and Bioscience, 2023 Background Drug resistance is a particular problem in patients with temporal lobe epilepsy, where seizures originate mainly from the hippocampus. Many of these epilepsies are acquired conditions following an insult to the brain such as a prolonged seizure. Such conditions are characterized by pathophysiological mechanisms including massive oxidative stress that synergistically mediate the secondary brain damage, contributing to the development of epilepsy. The transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2) has emerged in recent years as an attractive therapeutic approach targeting to upregulate the antioxidative defenses in the cell, to ameliorate the oxidative stress-induced damage. Thus, it is important to understand the characteristics of Nrf2 activation during epileptogenesis and epilepsy. Here, we studied the temporal, regional, and cell-type specific expression of Nrf2 in the brain, in a rat model of temporal lobe epilepsy. Results Early after status-epilepticus, Nrf2 is mainly activated in the hippocampus and maintained during the whole period of epileptogenesis. Only transient expression of Nrf2 was observed in the cortex. Nevertheless, the expression of several Nrf2 antioxidant target genes was increased within 24 h after status-epilepticus in both the cortex and the hippocampus. We demonstrated that after status-epilepticus in rats, Nrf2 is predominantly expressed in neurons in the CA1 and CA3 regions of the hippocampus, and only astrocytes in the CA1 increase their Nrf2 expression. Conclusions In conclusion, our data identify previously unrecognized spatial and cell-type dependent activation of Nrf2 during epilepsy development, highlighting the need for a time-controlled, and cell-type specific activation of the Nrf2 pathway for mediating anti-oxidant response after brain insult, to modify the development of epilepsy.
Repurposing dimethyl fumarate as an antiepileptogenic and disease-modifying treatment for drug-resistant epilepsy Sereen Sandouka, Prince Kumar Singh, Aseel Saadi, Rhoda Olowe Taiwo, Yara Sheeni, et al. Journal of Translational Medicine, 2023 Background Epilepsy affects over 65 million people worldwide and significantly burdens patients, caregivers, and society. Drug-resistant epilepsy occurs in approximately 30% of patients and growing evidence indicates that oxidative stress contributes to the development of such epilepsies. Activation of the Nrf2 pathway, which is involved in cellular defense, offers a potential strategy for reducing oxidative stress and epilepsy treatment. Dimethyl fumarate (DMF), an Nrf2 activator, exhibits antioxidant and anti-inflammatory effects and is used to treat multiple sclerosis. Methods The expression of Nrf2 and its related genes in vehicle or DMF treated rats were determined via RT-PCR and Western blot analysis. Neuronal cell death was evaluated by immunohistochemical staining. The effects of DMF in preventing the onset of epilepsy and modifying the disease were investigated in the kainic acid-induced status epilepticus model of temporal lobe epilepsy in rats. The open field, elevated plus maze and T-Maze spontaneous alteration tests were used for behavioral assessments. Results We demonstrate that administration of DMF following status epilepticus increased Nrf2 activity, attenuated status epilepticus-induced neuronal cell death, and decreased seizure frequency and the total number of seizures compared to vehicle-treated animals. Moreover, DMF treatment reversed epilepsy-induced behavioral deficits in the treated rats. Moreover, DMF treatment even when initiated well after the diagnosis of epilepsy, reduced symptomatic seizures long after the drug was eliminated from the body. Conclusions Taken together, these findings suggest that DMF, through the activation of Nrf2, has the potential to serve as a therapeutic target for preventing epileptogenesis and modifying epilepsy.
Nrf2 is expressed more extensively in neurons than in astrocytes following an acute epileptic seizure in rats Sereen Sandouka, Aseel Saadi, Rhoda Olowe, Prince Kumar Singh, Tawfeeq Shekh‐Ahmad Journal of Neurochemistry, 2023 The modulation of the nuclear factor erythroid 2‐like 2 (Nrf2) activity has been reported to be implicated in the pathology of various neurological disorders, including epilepsy. Previous studies have demonstrated that Nrf2 is activated in the post‐status epilepticus rat model; however, the spatiotemporal as well as cell type‐specific expression of Nrf2 following brief epileptic seizures remains unclear. Here, we evaluated how an acute epileptic seizure affected the expression of Nrf2 and its downstream genes in the rats' cortex and the hippocampus up to 1 week following the induced seizure. We found that after a pentylenetetrazol‐induced seizure, Nrf2 significantly increased at 24 h at the mRNA level and 3 h at the protein level in the cortex. In the hippocampus, the Nrf2 mRNA level peaked at 3 h after the seizure, and no significant changes were observed in the protein level. Interestingly, the mRNA level of Nrf2 downstream genes peaked at 3–6 h after seizure in both the cortex and the hippocampus. A significant increase in the expression of Nrf2 was observed in the neuronal population of CA1 and CA3 regions of the hippocampus, as well as in the cortex. Moreover, we observed no change in the co‐localization of Nrf2 with astrocytes neither in the cortex nor in CA1 and CA3. Our results revealed that following a brief acute epileptic seizure, the expression of Nrf2 and its downstream genes is transiently increased and peaked at early timepoints after the seizure predominantly in the hippocampus, and this expression is restricted to the neuronal population.
