An Insight into Molecular Mechanisms and Novel Therapeutic Approaches in Epileptogenesis

Glial Alterations in the Glutamatergic and GABAergic Signalling Pathways in a Mouse Model of Lafora Disease, a Severe Form of Progressive Myoclonus Epilepsy

AIMS

Lafora disease (LD; OMIM#254780) is a rare form of progressive myoclonus epilepsy characterised by the accumulation of insoluble deposits of glycogen in the brain and peripheral tissues. In mouse models of LD, we have identified neuroinflammation as a secondary hallmark of the disease, characterised by increased levels of reactive astrocytes and activated microglia. Our previous work demonstrated that the TNF and IL-6 inflammatory signalling pathways are the primary drivers of this neuroinflammatory phenotype. In this work, we aimed to investigate whether TNF and IL-6 pathway activation contributes to alterations in the glutamatergic and GABAergic signalling pathways.

METHODS

We performed immunofluorescence and western blot analyses on the hippocampus of a mouse model of LD to evaluate potential changes in proteins associated with glutamatergic and GABAergic signalling pathways.

RESULTS

Our findings reveal dysregulation in the expression of subunits of excitatory glutamatergic receptors (phospho-GluN2B and GluK2), as well as an increase in the levels of the GABA transporter GAT1. In addition, we detected activated forms of the Src and Lyn protein kinases in the hippocampus. More importantly, these alterations predominantly occur in nonneuronal cells, such as reactive astrocytes and microglia, underscoring the critical involvement of glial cells in the pathophysiology of LD.

CONCLUSIONS

The observed upregulation of glutamatergic receptor subunits likely amplifies excitatory glutamatergic signalling, whereas the increased expression of GAT1 may reduce the inhibitory GABAergic tone. These changes contribute to the characteristic hyperexcitability of LD.

Emerging targets in amyotrophic lateral sclerosis (ALS): The promise of ATP-binding cassette (ABC) transporter modulation

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative primarily affecting motor neurons, leading to disability and neuronal death, and ATP-Binding Cassette (ABC) transporter due to their role in drug efflux and modulation of various cellular pathways contributes to the pathogenesis of ALS. In this article, we extensively investigated various molecular and mechanistic pathways linking ALS transporter to the pathogenesis of ALS; this involves inflammatory pathways such as Mitogen-Activated Protein Kinase (MAPK), Phosphatidylinositol-3-Kinase/Protein Kinase B (PI3K/Akt), Toll-Like Receptor (TLR), Glycogen Synthase Kinase 3β (GSK-3β), Nuclear Factor Kappa-B (NF-κB), and Cyclooxygenase (COX). Oxidative pathways such as Astrocytes, Glutamate, Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), Sirtuin 1 (SIRT-1), Forkhead box protein O (FOXO), Extracellular signal-regulated kinase (ERK). Additionally, we delve into the role of autophagic pathways like TAR DNA-binding protein 43 (TDP-43), AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), and lastly, the apoptotic pathways. Furthermore, by understanding these intricate interactions, we aim to develop novel therapeutic strategies targeting ABC transporters, improving drug delivery, and ultimately offering a promising avenue for treating ALS.

Unveiling the Complexities: Exploring Mechanisms of Anthracyclineinduced Cardiotoxicity

The coexistence of cancer and heart disease, both prominent causes of illness and death, is further exacerbated by the detrimental impact of chemotherapy. Anthracycline-induced cardiotoxicity is an unfortunate side effect of highly effective therapy in treating different types of cancer; it presents a significant challenge for both clinicians and patients due to the considerable risk of cardiotoxicity. Despite significant progress in understanding these mechanisms, challenges persist in identifying effective preventive and therapeutic strategies, rendering it a subject of continued research even after three decades of intensive global investigation. The molecular targets and signaling pathways explored provide insights for developing targeted therapies, emphasizing the need for continued research to bridge the gap between preclinical understanding and clinical applications. This review provides a comprehensive exploration of the intricate mechanisms underlying anthracycline-induced cardiotoxicity, elucidating the interplay of various signaling pathways leading to adverse cellular events, including cardiotoxicity and death. It highlights the extensive involvement of pathways associated with oxidative stress, inflammation, apoptosis, and cellular stress responses, offering insights into potential and unexplored targets for therapeutic intervention in mitigating anthracycline-induced cardiac complications. A comprehensive understanding of the interplay between anthracyclines and these complexes signaling pathways is crucial for developing strategies to prevent or mitigate the associated cardiotoxicity. Further research is needed to outline the specific contributions of these pathways and identify potential therapeutic targets to improve the safety and efficacy of anthracycline-based cancer treatment. Ultimately, advancements in understanding anthracycline-induced cardiotoxicity mechanisms will facilitate the development of more efficacious preventive and treatment approaches, thereby improving outcomes for cancer patients undergoing anthracycline-based chemotherapy.

Anacyclus pyrethrum enhances fertility in cadmium-intoxicated male rats by improving sperm functions

BACKGROUND

Environmental pollutants, particularly heavy metals, have been frequently connected to male infertility. Cadmium was previously shown to reduce male fertility by causing oxidative stress. Anacyclus pyrethrum is a well-known medicinal plant. Most of its parts, notably the roots, have excellent antioxidant and anti-inflammatory properties. The present study investigated the potential ability of Anacyclus pyrethrum to protect male rats against cadmium reproductive toxicity.

METHODS

Twenty-eight adult Wistar male rats (8 weeks old) weighing (170-200g) were randomly divided into four groups (n = 7): group (1) the control, group (2) was orally administrated with Anacyclus pyrethrum extract (100mg/kg) for 56 consecutive days, group (3) received a single intraperitoneal (IP) injection of cadmium chloride (1mg/kg), and group (4) received a single IP dose of CdCl2 followed by 8 weeks of oral Anacyclus extract treatment.

RESULTS

Cadmium Cd toxicity resulted in a significant decrease in the concentration of antioxidant enzymes (superoxide dismutase SOD and glutathione peroxidase GPx) in the semen coupled with a significant rise in malondialdehyde MDA level. Consequently, sperm analysis parameters were significantly affected showing decreased motility, viability, concentration and increased morphological aberrations. DNA fragmentation was also detected in the sperms of rats exposed to Cd using comet assay. Serum levels of testosterone T, follicle stimulating hormone FSH, and luteinizing hormone LH were significantly decreased. The mRNA expression levels of sex hormone receptors (FSHR, LHR and AR) in the testis of the Cd exposed rats were significantly decreased. Expression levels of Bax and Bcl2 genes in the sperms of Cd intoxicated rats were also affected shifting the Bax/Bcl2 ratio towards the induction of apoptosis. Co-treatment with the Anacyclus pyrethrum extract restored the oxidative enzymes activities and decreased the formation of lipid peroxidation byproduct, which in turn ameliorated the effect of Cd on sperm parameters, sperm DNA damage, circulating hormone levels, gene expression and apoptosis. These results indicate that Anacyclus pyrethrum could serve as a protective agent against cadmium-induced sperm toxicity.

CONCLUSION

Taken together, it can be concluded that the antioxidant activities of Anacyclus pyrethrum restored the semen quality and enhanced fertility in Cd-intoxicated male rats.

Pharmacological perspectives and mechanisms involved in epileptogenesis

Background

Epileptogenesis can be defined as the process by which a previously healthy brain develops a tendency toward recurrent electrical activity, occurring in three phases: first as an initial trigger (such as stroke, infections, and traumatic brain injury); followed by the latency period and the onset of spontaneous and recurrent seizures which characterizes epilepsy.

Main body

The mechanisms that may be involved in epileptogenesis are inflammation, neurogenesis, migration of neurons to different regions of the brain, neural reorganization, and neuroplasticity.In recent years, experimental studies have enabled the discovery of several mechanisms involved in the process of epileptogenesis, mainly neuroinflammation, that involves the activation of glial cells and an increase in specific inflammatory mediators. The lack of an experimental animal model protocol for epileptogenic compounds contributes to the difficulty in understanding disease development and the creation of new drugs.

Conclusion

To solve these difficulties, a new approach is needed in the development of new AEDs that focus on the process of epileptogenesis and the consolidation of animal models for studies of antiepileptogenic compounds, aiming to reach the clinical phases of the study. Some examples of these compounds are rapamycin, which inhibits mTOR signaling, and losartan, that potentiates the antiepileptogenic effect of some AEDs. Based on this, this review discusses the main mechanisms involved in epileptogenesis, as well as its pharmacological approach.

The functional mechanisms of synchronizing royal jelly consumption and physical activity on rat with multiple sclerosis-like behaviors hallmarks based on bioinformatics analysis, and experimental survey

Background

Natural nutrition and physical training have been defined as non-pharmacochemical complementary and alternative medicines to prevent and treat various pathogenesis. Royal jelly possesses various pharmacological properties and is an effective therapeutic supplement for halting neurodegeneration. Multiple sclerosis is a prevalent neurodegenerative disorder that manifests as a progressive neurological condition. Inflammation, hypoxia, and oxidative stress have been identified as significant hallmarks of multiple sclerosis pathology.

Results

In the present study, based on artificial intelligence and bioinformatics algorithms, we marked hub genes, molecular signaling pathways, and molecular regulators such as non-coding RNAs involved in multiple sclerosis. Also, microRNAs as regulators can affect gene expression in many processes. Numerous pathomechanisms, including immunodeficiency, hypoxia, oxidative stress, neuroinflammation, and mitochondrial dysfunction, can play a significant role in the MSc pathogenesis that results in demyelination. Furthermore, we computed the binding affinity of bioactive compounds presented in Royal Jelly on macromolecules surfaces. Also, we predicted the alignment score of bioactive compounds over the pharmacophore model of candidate protein as a novel therapeutic approach. Based on the q-RT-PCR analysis, the expression of the Dnajb1/Dnajb1/Foxp1/Tnfsf14 and Hspa4 networks as well as miR-34a-5p and miR155-3p were regulated by the interaction of exercise training and 100 mg/kg Royal Jelly (ET-100RJ). Interestingly, characteristics, motor function, a proinflammatory cytokine, and demyelination were ameliorated by ET-100RJ.

Discussion

Here, we indicated that interaction between exercise training and 100 mg/kg Royal jelly had a more effect on regulating the microRNA profiles and hub genes in rats with Multiple sclerosis.

Demethyleneberberine, a potential therapeutic agent in neurodegenerative disorders: a proposed mechanistic insight

INTRODUCTION

Neurodegenerative disorders are a diverse variety of diseases that can be distinguished from developing degeneration of neurons in the CNS. Several alkaloids have shown mounting effects in neurodegenerative disorders, and berberine is one of them. Demethyleneberberine is a metabolite of berberine that has better blood-brain barrier crossing capacity. Demethyleneberberine possesses anti-inflammatory, anti-oxidant, and mitochondrial targeting properties. However, neither the pharmacological action nor the molecular mechanism of action of demethyleneberberine on neurodegenerative disorders has been explored yet.

MATERIALS AND METHODS

A systematic literature review of PubMed, Medline, Bentham, Scopus, and EMBASE (Elseveier) databases was carried out with the help of keywords like "Demethyleneberberine; neuroinflammation; oxidative stress; Neuroprotective; Neurodegenerative disorders" till date.

CONCLUSION

This review focus on the neuroprotective potential of demethyleneberberine in neurodegenerative disorders by attenuating different pathways, i.e., NF-κB, MAPK, and AMPK signalling.

α-Lipoic Acid, an Organosulfur Biomolecule a Novel Therapeutic Agent for Neurodegenerative Disorders: An Mechanistic Perspective

Lipoic acid (α-LA) (1,2-dithiolane3-pentanoic acid (C₈H₁₄O₂S₂) is also called thioctic acid with an oxidized (disulfide, LA) and a reduced (di-thiol: dihydro-lipoic acid, DHLA) form of LA. α-LA is a potent anti-oxidative agent that has a significant potential to treat neurodegenerative disorders. α-LA is both hydrophilic and hydrophobic in nature. It is widely distributed in plants and animals in cellular membranes and in the cytosol, which is responsible for LA's action in both the cytosol and plasma membrane. A systematic literature review of Bentham, Scopus, PubMed, Medline, and EMBASE (Elsevier) databases was carried out to understand the Nature and mechanistic interventions of the α-Lipoic acid for central nervous system diseases. Moreover, α-LA readily crosses the blood-brain barrier, which is a significant factor for CNS activities. The mechanisms of α-LA reduction are highly tissue-specific. α-LA produces its neuroprotective effect by inhibiting reactive oxygen species formation and neuronal damage, modulating protein levels, and promoting neurotransmitters and anti-oxidant levels. Hence, the execution of α-LA as a therapeutic ingredient in the therapy of neurodegenerative disorders is promising. Finally, based on evidence, it can be concluded that α-LA can prevent diseases related to the nervous system.

Ultrasonic Assisted Synthesis, Biological Evaluation, and Molecular Docking of Chalcone-based 1,5-benzodiazepine as Potential Anticonvulsant Agents

Background:

Epilepsy is a constant neurological disorder influencing around 50 million individuals globally. However, most epileptic patients do not react to accessible medications and clinical treatments. This research work has been planned to produce novel 1,5-benzodiazepines from chalcone intermediates by ultrasonic irradiation method and perform the anticonvulsant activity by pentylenetetrazole incited seizures tests.

Method:

Chalcones are used as precursors for synthesizing 1, 5-benzodiazepines by a reaction with ophenylenediamine in absolute ethanol in the presence of glacial acetic acid as a catalyst. The proposed synthesized structures were characterized by melting point, TLC, FTIR, 1H & 13CNMR, and mass spectroscopy. All the molecules were assessed for anticonvulsant activity.

Result:

Anticonvulsant activity uncovered the fact that the mixes derived from dimethylamino, dimethoxy, hydroxy-substituted chalcones in the 1, 5-benzodiazepines can be used for seizures in mice. These pharmacological examinations have shown that these new subsidiaries can repress seizures incited by pentylenetetrazole in mice proficiently. Our molecular docking studies also supported probable effects.

Conclusion:

The results are promising, which on further assessments may provoke medicine particles against seizures in mice.

Anticonvulsive Effects of Chondroitin Sulfate on Pilocarpine and Pentylenetetrazole Induced Epileptogenesis in Mice

Chondroitin sulfate is a proteoglycan component of the extracellular matrix (ECM) that supports neuronal and non-neuronal cell activity, provides a negative domain to the extracellular matrix, regulates the intracellular positive ion concentration, and maintains the hypersynchronous epileptiform activity. Therefore, the present study hypothesized an antiepileptic potential of chondroitin sulfate (CS) in pentylenetetrazole-induced kindled epilepsy and pilocarpine-induced status epilepticus in mice. Levels of various oxidative stress markers and inflammatory mediators were estimated in the brain tissue homogenate of mice, and histopathological changes were evaluated. Treatment with valproate (110 mg/kg; i.p.) as a standard drug and chondroitin sulfate (100 & 200 mg/kg, p.o.) significantly (p < 0.01) and dose-dependently prevented the severity of kindled and spontaneous recurrent seizures in mice. Additionally, chondroitin sulfate showed its antioxidant potential by restoring the various biochemical levels and anti-inflammatory properties by reducing NF-kB levels and pro-inflammatory mediators like TNF-alpha, IL-1β, and IL-6, indicating the neuroprotective effect as well as the suppressed levels of caspase-3, which indicated a neuroprotective treatment strategy in epilepsy. The proteoglycan chondroitin sulfate restores the normal physiology and configuration of the neuronal tissue. Further, the molecular docking of chondroitin sulfate at the active pockets of TNF-alpha, IL-1β, and IL-6 showed excellent interactions with critical amino acid residues. In conclusion, the present work provides preclinical evidence of chondroitin sulfate as a new therapeutic approach in attenuating and preventing seizures with a better understanding of the mechanism of alteration in ECM changes influencing abnormal neuronal activities.

Pharmacological modulation of cytokines correlating neuroinflammatory cascades in epileptogenesis

Epileptic seizure-induced brain injuries include activation of neuroimmune response with activation of microglia, astrocytes cells releasing neurotoxic inflammatory mediators underlies the pathophysiology of epilepsy. A wide spectrum of neuroinflammatory pathways is involved in neurodegeneration along with elevated levels of inflammatory mediators indicating the neuroinflammation in the epileptic brain. Therefore, the neuroimmune response is commonly observed in the epileptic brain, indicating elevated cytokine levels, providing an understanding of the neuroinflammatory mechanism contributing to seizures recurrence. Clinical and experimental-based evidence suggested the elevated levels of cytokines responsible for neuronal excitation and blood-brain barrier (BBB) dysfunctioning causing the drug resistance in epilepsy. Therefore, the understanding of the pathogenesis of neuroinflammation in epilepsy, including migration of microglial cells releasing the inflammatory cytokines indicating the correlation of elevated levels of inflammatory mediators (interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) triggering the generation or recurrence of seizures. The current review summarized the knowledge regarding elevated inflammatory mediators as immunomodulatory response correlating multiple neuroinflammatory NF-kB, RIPK, MAPK, ERK, JNK, JAK-STAT signaling cascades in epileptogenesis. Further selective targeting of inflammatory mediators provides beneficial therapeutic strategies for epilepsy.

Emerging perspectives on mitochondrial dysfunctioning and inflammation in epileptogenesis

INTRODUCTION

Mitochondrial dysfunction is a common denominator of neuroinflammation recognized by neuronal oxidative stress-mediated apoptosis that is well recognized by common intracellular molecular pathway-interlinked neuroinflammation and mitochondrial oxidative stress, a feature of epileptogenesis. In addition, the neuronal damage in the epileptic brain corroborated the concept of brain injury-mediated neuroinflammation, further providing an interlink between inflammation, mitochondrial dysfunction, and oxidative stress in epilepsy.

MATERIALS AND METHODS

A systematic literature review of Bentham, Scopus, PubMed, Medline, and EMBASE (Elsevier) databases was carried out to provide evidence of preclinical and clinically used drugs targeting such nuclear, cytosolic, and mitochondrial proteins suggesting that the correlation of mechanisms linked to neuroinflammation has been elucidated in the current review. Despite that, the evidence of elevated levels of inflammatory mediators and pro-apoptotic protein levels can provide the correlation of inflammatory responses often concerned with hyperexcitability attributing to the fact that mitochondrial redox mechanisms and higher susceptibilities to neuroinflammation result from repetitive recurring epileptic seizures. Therefore, providing an understanding of seizure-induced pathological changes read by activating neuroinflammatory cascades like NF-kB, RIPK, MAPK, ERK, JNK, and JAK-STAT signaling further related to mitochondrial damage promoting hyperexcitability.

CONCLUSION

The current review highlights the further opportunity for establishing therapeutic interventions underlying the apparent correlation of neuroinflammation mediated mitochondrial oxidative stress might contribute to common intracellular mechanisms underlying a future prospective of drug treatment targeting mitochondrial dysfunction linked to the neuroinflammation in epilepsy.

Apoptotic Pathways and Alzheimer's Disease: Probing Therapeutic Potential

Apoptosis is an intrinsic biochemical, cellular process that regulates cell death and is crucial for cell survival, cellular homeostasis, and maintaining the optimum functional status. Apoptosis in a predetermined and programmed manner regulates several molecular events, including cell turnover, embryonic development, and immune system functions but may be the exclusive contributor to several disorders, including neurodegenerative manifestations, when it functions in an aberrant and disorganized manner. Alzheimer's disease (AD) is a fatal, chronic neurodegenerative disorder where apoptosis has a compelling and divergent role. The well-characterized pathological features of AD, including extracellular plaques of amyloid-beta, intracellular hyperphosphorylated tangles of tau protein (NFTs), inflammation, mitochondrial dysfunction, oxidative stress, and excitotoxic cell death, also instigate an abnormal apoptotic cascade in susceptible brain regions (cerebral cortex, hippocampus). The apoptotic players in these regions affect cellular organelles (mitochondria and endoplasmic reticulum), interact with trophic factors, and several pathways, including PI3K/AKT, JNK, MAPK, mTOR signalling. This dysregulated apoptotic cascade end with an abnormal neuronal loss which is a primary event that may precede the other events of AD progression and correlates well with the degree of dementia. The present review provides insight into the diverse and versatile apoptotic mechanisms that are indispensable for neuronal survival and constitute an integral part of the pathological progression of AD. Identification of potential targets (restoring apoptotic and antiapoptotic balance, caspases, TRADD, RIPK1, FADD, TNFα, etc.) may be valuable and advantageous to decide the fate of neurons and to develop potential therapeutics for treatment of AD.

Reviving mitochondrial bioenergetics: A relevant approach in epilepsy

Epileptogenesis is most commonly associated with neurodegeneration and a bioenergetic defect attributing to the fact that mitochondrial dysfunction plays a key precursor for neuronal death. Mitochondria are the essential organelle of neuronal cells necessary for certain neurophysiological processes like neuronal action potential activity and synaptic transmission. The mitochondrial dysfunction disrupts calcium homeostasis leading to inhibitory interneuron dysfunction and increasing the excitatory postsynaptic potential. In epilepsy, the prolonged repetitive neuronal activity increases the excessive demand for energy and acidosis in the brain further increasing the intracellular calcium causing neuronal death. Similarly, the mitochondrial damage also leads to the decline of energy by dysfunction of the electron transport chain and abnormal production of the ROS triggering the apoptotic neuronal death. Thus, the elevated level of cytosolic calcium causes the mitochondria DNA damage coinciding with mtROS and releasing the cytochrome c binding to Apaf protein further initiating the apoptosis resulting in epileptic encephalopathies. The various genetic and mRNA studies of epilepsy have explored the various pathogenic mutations of genes affecting the mitochondria functioning further initiating the neuronal excitotoxicity. Based on the results of previous studies, the recent therapeutic approaches are targeting basic mitochondrial processes, such as energy metabolism or free-radical generation, or specific interactions of disease-related proteins with mitochondria and hold great promise to attenuate epileptogenesis. Therefore, the current review emphasizes the emerging insights to uncover the relation between mitochondrial dysfunction and ROS generation contributing to mechanisms underlying epileptic seizures.