Neurodegenerative diseases and oxidative stress

Nuclear translocation of the LINE-1 encoded ORF1 protein alters nuclear envelope integrity in human neurons

LINE-1 retrotransposons are increasingly implicated in aging and neurodegenerative diseases, yet the precise pathogenic mechanisms remain elusive. While the endonuclease and reverse transcriptase activities of LINE-1-encoded ORF2p can induce DNA damage and inflammation, a role of LINE-1 ORF1p in cellular dysfunctions stays unassigned. Here we demonstrate, using a neuronal cellular model, that ORF1p translocates into the nucleus upon arsenite-induced stress, directly interacting with nuclear import (KPNB1), nuclear pore complex (NUP153), and nuclear lamina (Lamin B1) proteins. Nuclear translocation of ORF1p disrupts nuclear integrity, nucleocytoplasmic transport, and heterochromatin structure, features linked to neurodegeneration and aging. Elevated nuclear ORF1p levels induced either by arsenite-induced stress, ORF1p overexpression, or as observed in Parkinson's disease post-mortem brain tissues correlate with impaired nuclear envelope (NE) morphology. Stress-induced nuclear alterations are mitigated by blocking ORF1p nuclear import or with the anti-aging drug remodelin. This study thus reveals a pathogenic action of nuclear ORF1p in human neurons driving NE alterations and thereby contributing to LINE-1-mediated cell toxicity.

Ethanol-Induced Depression: Exploring the Underlying Molecular Mechanisms

Ethanol consumption is widely recognized for its detrimental effects on mental health, particularly its association with depressive disorders. This narrative review aims to explore the intricate molecular mechanisms underlying ethanol-induced depression, synthesizing findings from preclinical and clinical studies. We begin by providing an overview of the relationship between chronic ethanol consumption and depression, highlighting compelling evidence from diverse populations. Subsequently, we delve into insights from animal models that elucidate the pathophysiological changes triggered by prolonged ethanol exposure. Key mechanisms identified include oxidative stress, which contributes to cellular damage; neuroinflammation, characterized by the activation of glial cells and altered cytokine profiles; and disruptions in neurotrophic factors that impair neuronal growth and survival. Furthermore, we discuss the induction of apoptosis in neural cells and the significant impact of ethanol on neurotransmitter receptor remodeling and regulation, leading to altered synaptic transmission. While substantial progress has been made in understanding these mechanisms, we also acknowledge the limitations of current research methodologies and call for further investigations to translate these findings into effective therapeutic strategies for individuals affected by ethanol-induced depression. This review ultimately underscores the need for a comprehensive understanding of the molecular underpinnings of ethanol's impact on mood disorders, paving the way for improved interventions and preventative measures.

Asiatic acid and its derivatives: Pharmacological insights and applications

Centella asiatica (L.) Urban has been utilized in wound healing remedies for nearly 3000 years. Asiatic acid (AA), a pentacyclic triterpenoid characterized by ursane-type skeleton, serves as principal bioactive constituent of Centella asiatica, exhibits remarkable therapeutic potential across a spectrum of health conditions. Pharmacological investigations have revealed that AA exerts direct regulatory effects on a multitude of enzymes, receptors, inflammatory mediators, and transcription factors. This article systematically examines the therapeutic applications of AA and its derivatives in the management of neurodegenerative diseases, cancer, cardiovascular disorders, and infections. Additionally, recent advancements in the structural modification of AA are summarized, offering new insights for the development of low-toxicity, effective AA-based therapeutics and diagnostic agents. However, several challenges remain, including the paucity of clinical trials, uncertainties in dosage and treatment regimens, limited data on long-term safety and side effects, and poor bioavailability. Addressing these limitations is crucial for advancing AA-based therapies and ensuring their clinical applicability.

Computational drug repurposing in Parkinson's disease: Omaveloxolone and cyproheptadine as promising therapeutic candidates

Background: Parkinson's disease (PD), a prevalent and progressive neurodegenerative disorder, currently lacks effective and satisfactory pharmacological treatments. Computational drug repurposing represents a promising and efficient strategy for drug discovery, aiming to identify new therapeutic indications for existing pharmaceuticals. Methods: We employed a drug-target network approach to computationally repurpose FDA-approved drugs from databases such as DrugBank. A literature review was conducted to select candidates not previously reported as pharmacoprotective against PD. Subsequent in vitro evaluation utilized Cell Counting Kit-8 (CCK8) assays to assess the neuroprotective effects of the selected compounds in the SH-SY5Y cell model of Parkinson's disease induced by 1-methyl-4-phenylpyridinium (MPP+). Furthermore, an in vivo mouse model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was developed to investigate the mechanisms of action and therapeutic potential of the identified drug candidates. Results: Our approach identified 176 drug candidates, with 28 selected for their potential anti-Parkinsonian effects and lack of prior PD-related reporting. CCK8 assays showed significant neuroprotection in SH-SY5Y cells for Omaveloxolone and Cyproheptadine. In the MPTP-induced mouse model, Cyproheptadine inhibited interleukin-6 (IL-6) expression and prevented Tyrosine Hydroxylase (TH) downregulation via the MAPK/NFκB pathway, while Omaveloxolone alleviated TH downregulation, potentially through the Kelch-like ECH-associated protein 1 (KEAP1)-NF-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway. Both drugs preserved dopaminergic neurons and improved neurological deficits in the PD model. Conclusion: This study elucidates potential drug candidates for the treatment of Parkinson's disease through the application of computational repurposing, thereby underscoring its efficacy as a drug discovery strategy.

TCE-mediated neuroprotection against rotenone-induced dopaminergic neuronal death in PD mice: insights into the Nrf-2/PINK1/Parkin-mitophagy pathway

Oxidative stress-induced mitochondrial dysfunction is implicated in the pathogenesis of Parkinson's disease (PD). In a previous study, we reported that an extract of T. cordifolia (TCE) possessed antioxidant and anti-apoptotic properties that improved mitochondrial function against rotenone-induced neurotoxicity. However, the underlying molecular mechanism remains unclear. In this study, we found that rotenone (ROT)-induced PD mice exhibited mitochondrial abnormalities, including defective mitophagy, mitochondrial reactive oxygen species (ROS) overexpression, and mitochondrial fragmentation, accompanied by reduced expression of Pink1 and Parkin and increased apoptosis. These changes were partially reversed following oral administration of TCE. Moreover, TCE restored the activity and translocation of NF-E2-related factor 2 (Nrf2) and upregulated the expression of antioxidant enzymes (SOD1, SOD2, GSH, and GSSH). Interestingly, ROT also activates mitophagy. Our results suggest that ROT toxicity can cause neuronal cell death through mitophagy-mediated signaling in PD mice. However, TCE reversed this activity by inhibiting autophagic protein (LC3B-II/LC3B-I) activation and increasing specific mitochondrial proteins (TOM20, Pink1, and Parkin). Our findings indicated that TCE provides neuroprotection against rotenone-induced toxicity in PD mice by stimulating endogenous antioxidant enzymes and inhibiting ROT-induced oxidative stress by potentiating the Nrf-2/Pink1/Parkin-mediated survival mechanism.

A water-soluble glucose-appended quinoline-benzothiazole conjugate as a selective and sensitive receptor for Cu+ ions in aqueous media and intracellular bio-imaging in live cells

A water-soluble and biologically benign glucose-appended quinoline-benzothiazole conjugate (L) has been synthesized and characterized using various spectroscopy techniques. The recognition properties of L show selective recognition of Cu+ ions among other biological metal ions including Cu2+ ions in PBS buffer at pH 7.4. L exhibited a switch-on fluorescence enhancement upon the addition of Cu+ with a detection limit of 1.48 × 10-8 M in an aqueous medium. Job's plot confirmed the 1 : 1 binding ratio observed between probe L and Cu+ ions with an association constant (Ka) of 1.46 × 105 M-1. The proposed complex binding mechanism was supported by UV-Vis, fluorescence and ESI-MS. The coordination features of the {L + Cu+} complex were delineated using DFT computational calculations. Furthermore, L was successfully applied for intracellular fluorescence bio-imaging of Cu+ ions in L929 living cells, suggesting that it holds significant potential for Cu+ ion bio-imaging and disease diagnosis.

Functionalized Green Carbon dots for Specific Detection of Copper in Human Serum Samples and Living Cells

Intracellular copper ion (Cu2+) is irreplaceable and essential in regulation of physiological and biological processes, while excessive copper from bioaccumulation may cause potential hazards to human health. Hence, effective and sensitive recognition is urgently significant to prevent over-intake of copper. In this work, a novel highly sensitive and green carbon quantum dots (Green-CQDs) were synthesized by a low-cost and facile one-step microwave auxiliary method, which utilized gallic acid, carbamide and PEG400 as carbon source, nitrogen source and surface passivation agent, respectively. The decreased fluorescence illustrated excellent linear relationship with the increasing of Cu2+ concentration in a wide range. Substantial surface amino and hydroxyl group introduced by PEG400 significantly improved selectivity and sensitivity of Green-CQDs. The surface amino chelation mechanism and fluorescence internal filtration effect were demonstrated by the restored fluorescence after addition of EDTA. Crucially, the nanosensor illustrated good cell permeability, high biocompatibility and recovery rate, significantly practical application in fluorescent imaging and biosensing of intracellular Cu2+ in HepG-2 cells, which revealed a potential and promising biological applications in early diagnosis and treatment of copper ion related disease.

Effective Detection of Cu(II) Ions Based on Carbon Dots@Exfoliated Layered Double Hydroxides Composites Fluorescence Probe

A series of carbon dots@exfoliated layered double hydroxides (CDs@LDH) composites were hydrothermally fabricated by Mg/Al LDH and formamide. The results of FTIR, UV-vis, and XPS spectra in company with HRTEM images showed that crystalline nano CDs formed on the single layer of LDH by Mg-C bond. With the increase of solvothermal reaction time from 2 to 6 h, the band gap and the binding energy of aminic and graphitic N species of CDs@LDH composites decreased, whereas the crystallinity increased. The fluorescence peaks of CDs@LDH composites could be deconvoluted into short-wavelength (416 nm) and large-wavelength (443 nm) components by Gaussian function, and the fluorescence intensities of both components enhanced with the extension of the solvothermal reaction time. The simultaneous enhancements of fluorescence lifetime and quantum yield resulted from the relatively high electron density in graphitic nitrogen of CDs@LDH, whereas the reduction of nonradiative rate was due to the high crystallinity in the carbon core of CDs@LDH. A strong exciton-lattice interaction also has been validated based on the excitation and emission spectra of CDs@LDH, so the fluorescence emission of CDs@LDH composite was heavily related to its crystalline carbon core and nitrogen-containing groups. CDs@LDH with high nitrogen-containing exhibited a superior detection property for Cu2+ ion sensing with the linear range of 26.90 ~ 192.20 μM and a limit of detection of 0.1957 μM. The photo-induced electron transfer (PET) process dominated the fluorescence quenching of CDs@LDH by Cu2+ ion since the fluorescence lifetime decreased with the increase of Cu2+ ion concentration.

Glial cells improve Parkinson's disease by modulating neuronal function and regulating neuronal ferroptosis

The main characteristics of Parkinson's disease (PD) are the loss of dopaminergic (DA) neurons and abnormal aggregation of cytosolic proteins. However, the exact pathogenesis of PD remains unclear, with ferroptosis emerging as one of the key factors driven by iron accumulation and lipid peroxidation. Glial cells, including microglia, astrocytes, and oligodendrocytes, serve as supportive cells in the central nervous system (CNS), but their abnormal activation can lead to DA neuron death and ferroptosis. This paper explores the interactions between glial cells and DA neurons, reviews the changes in glial cells during the pathological process of PD, and reports on how glial cells regulate ferroptosis in PD through iron homeostasis and lipid peroxidation. This opens up a new pathway for basic research and therapeutic strategies in Parkinson's disease.

Neuroprotective effects of fermented blueberry and black rice against particulate matter 2.5 μm-induced inflammation in vitro and in vivo

The increasing prevalence of particulate matter (PM) has raised significant concerns about its adverse effects on human health. This study investigates the potential of fermented blueberry and black rice (FBBR) in mitigating the effects of PM2.5 in SH-SY5Y cells and mice. Various assays, including MTT, NO, western blot, ELISA, and behavioral studies were conducted. Results showed that PM2.5 induced considerable cytotoxicity and elevated NO production at a concentration of 100 μg/mL of PM2.5 in SH-SY5Y cells. FBBR administration attenuated PM2.5-exposed cytotoxicity and suppressed NO production in SH-SY5Y cells. In an intranasally-exposed mice model, 10 mg/kg body weight (BW) of PM2.5 resulted in cognitive impairments. However, FBBR treatment ameliorated these impairments in both the Y-maze and MWM tests in PM2.5-exposed mice. Additionally, FBBR administration increased the expression of BDNF and reduced inflammatory markers in the brains of PM2.5-exposed SH-SY5Y cells. These findings highlight the detrimental effects of PM2.5 on the nervous system and suggest the potential of FBBR as a nutraceutical agent for mitigating these effects. Importantly, the results emphasize the urgency of addressing the harmful impact of PM2.5 on the nervous system and underscore the promising role of FBBR as a protective intervention against the adverse effects associated with PM2.5 exposure.

Neuroprotective Assessment of Nutraceutical (Betanin) in Neuroblastoma Cell Line SHSY-5Y: An in-Vitro and in-Silico Approach

The cognitive dysfunction in the brain cause severe pathological consequences such as Alzheimer's disease (AD), Parkinson's disease. The current treatments are cost expensive and also cause negative side effects. Therefore it is inevitable to develop natural phyto-compounds as a drug like molecules to treat neurodegenerative diseases. In this context, we have assayed the neuroprotective effects of betanin, an indole derivative, in the neuroblastoma cell line SHSY-5Y cells. The neuroprotective effect was investigated in the β-amyloid (Aβ) - induced SHSY-5Y cells; betanin (25 µg) protected the SHSY-5Y cells from the toxic effects and maintained the cell viability. Moreover, the acridine orange and ethidum Bromide staining decipher that treatment of betanin in the Aβ-induced SHSY-5Y cells maintain the cell viablity sustainably. The Reactive Oxygen Species (ROS) assay infers that betanin quenches the generation of free radicals progressively in the Aβ-induced SHSY-5Y cells. In addition, the autophagy determination by flow cytometry revealed that betanin induces autophagy to remove the neurodegenerated cells. Further, we examined the docking and simulation patterns with the angiotensin-converting enzyme (ACE), TNF-α converting enzyme (TACE), glycogen synthase kinase 3 (GK3), and acetylcholinesterase enzymes (AChE) and amyloid precursor protein (APP). The insilico docking analysis denotes that betanin had a significant docking score with the target molecules. Thus, from the invitro and insilico studies, betanin strongly inhibit the toxic effects of Aβand protect the cells from degeneration.

Robust In Vitro Models for Studying Parkinson's Disease? LUHMES Cells and SH-SH5Y Cells

As our population ages, there is an increased unmet clinical need surrounding neurodegenerative diseases such as Parkinson's disease (PD). To tackle this ever-increasing problem, we must ensure that the cell models that we use to develop therapeutics in vitro are robust, reliable, and replicable. In this study, we compared SH-SY5Y cells with LUHMES cells in response to 6-Hydroxydopamine (6OHDA) and 1-Methyl-4-phenylpyridinium (MPP+), two common Parkinson's insults used in in vitro analysis. Both these cell types have apparent dopaminergic phenotypes, which could aid us in understanding their potential in this race to novel therapies. The LUHMES cells showed consistent dopaminergic (DA) expression through tyrosine hydroxylase (TH) positivity, alongside depleted ATP levels and elevated reactive oxygen species (ROS) production, whereas the SH-SH5Y cells displayed resilience to both chemical insults, raising questions about their utility in accurately modelling PD pathology. Further electrophysiological analysis revealed comparable firing rates and ion channel signalling between both cell types; however, LUHMES cells demonstrated stronger calcium signalling responses, further supporting their use as a more robust PD model. While SH-SY5Y cells showed some adaptability in vitro, their inconsistent DA phenotype and limited response to chemical insults limit their suitability for advanced research, suggesting that LUHMES cells should and must take their place as a hallmark in Parkinson's disease research.

Intelligent Hydrogel with Physiologically Dependent Capacities of Photothermal Conversion and Nanocatalytic Medicine to Integratively Inhibit Bacteria and Inflammation for On-Demand Treatment of Infected Wound

Although chemodynamic therapy (CDT) and photothermal therapy (PTT) based on a variety of nanoparticles have been developed to achieve effective anti-bacterial therapy, the limited therapeutic efficiency of CDT alone, as well as the undifferentiated damage of PTT to both bacteria and surrounding healthy tissue are still challenges for their clinical application of infected wounds treatments. In addition, during the CDT and PTT-mediated antimicrobial processes, the endogenous macrophages would be easily converted to pro-inflammatory macrophages (M1 phenotype) under local ROS and hyperthermia to promote inflammation, resulting in unexpected suppression of tissue regeneration and possible wound deterioration. To address these problems, a biodegradable sodium alginate/hyaluronic acid hydrogel loaded with functional CeO2-Au nano-alloy (AO@ACP) is fabricated to not only achieve precise and efficient antibacterial activity through infection-environment dependent photothermal-chemodynamic therapy but also rapidly eliminate the excess reactive oxygens (ROS) in the M1 type macrophage at the infected area to induce their polarization to M2 type for significant inhibition of inflammation and remarkable enhancement of tissue regeneration, hopefully developing an effective strategy to treat infected wound.

Role of Oxidative Stress in Blood-Brain Barrier Disruption and Neurodegenerative Diseases

Upregulation of reactive oxygen species (ROS) levels is a principal feature observed in the brains of neurodegenerative diseases such as Parkinson's disease (PD) and Alzheimer's disease (AD). In these diseases, oxidative stress can disrupt the blood-brain barrier (BBB). This disruption allows neurotoxic plasma components, blood cells, and pathogens to enter the brain, leading to increased ROS production, mitochondrial dysfunction, and inflammation. Collectively, these factors result in protein modification, lipid peroxidation, DNA damage, and, ultimately, neural cell damage. In this review article, we present the mechanisms by which oxidative damage leads to BBB breakdown in brain diseases. Additionally, we summarize potential therapeutic approaches aimed at reducing oxidative damage that contributes to BBB disruption in neurodegenerative diseases.

Green synthesis of nanoparticles using medicinal plants as an eco-friendly and therapeutic potential approach for neurodegenerative diseases: a comprehensive review

Central nervous system disorders impact over 1.5 billion individuals globally, with neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's diseases being particularly prominent. These conditions, often associated with aging, present debilitating symptoms including memory loss and movement difficulties. The growing incidence of neurological disorders, alongside a scarcity of effective anti-amyloidogenic therapies, highlights an urgent need for innovative treatment methodologies. Nanoparticles (NPs), derived from medicinal plants and characterized by their favorable pharmacological properties and minimal side effects, offer a promising solution. Their inherent attributes allow for successful traversal of the blood-brain barrier (BBB), enabling targeted delivery to the brain and the modulation of specific molecular pathways involved in neurodegeneration. NPs are crucial in managing oxidative stress, apoptosis, and neuroinflammation in ND. This study reviews the efficacy of green-synthesized nanoparticles in conjunction with various medicinal plants for treating neurodegenerative diseases, advocating for further research to refine these formulations for enhanced clinical applicability and improved patient outcomes.

A Review on the Neuroprotective Effect of Moringa oleifera

Moringa oleifera, which is known as a drumstick tree in different areas of the world, is well-known for many health benefits, which are attributed to the abundance of flavonoids, phenolic chemicals, and thiocyanates it contains. This review focuses on M. oleifera's potential for neuroprotection, emphasizing its anti-inflammatory, antioxidant, and neurotransmitter-modulating qualities. Different parts of M. oleifera include leaves, roots, bark, and gum. Flowers, seeds, and seed oil are used for many health purposes, most notably in the treatment of neurological diseases. Neurodegeneration, which is characterized by the progressive death of nerve cells, is a major concern with an aging population, leading to disorders such as dementia and movement disorders. M. oleifera bioactive compounds improve the antioxidant defense activities of the brain, reduce inflammation, and improve neurotransmitter levels, showing potential therapeutic applications for neurodegenerative disorders. This review emphasizes the importance of further research, especially clinical trials, to fully understand and utilize M. oleifera's neuroprotective capabilities.

C9orf72 dipeptides activate the NLRP3 inflammasome

Frontotemporal dementia and amyotrophic lateral sclerosis are neurodegenerative diseases with considerable clinical, genetic and pathological overlap. The most common cause of both diseases is a hexanucleotide repeat expansion in C9orf72. The expansion is translated to produce five toxic dipeptides, which aggregate in patient brain. Neuroinflammation is a feature of frontotemporal dementia and amyotrophic lateral sclerosis; however, its causes are unknown. The nod-like receptor family, pyrin domain-containing 3 inflammasome is implicated in several other neurodegenerative diseases as a driver of damaging inflammation. The inflammasome is a multi-protein complex which forms in immune cells in response to tissue damage, pathogens or aggregating proteins. Inflammasome activation is observed in models of other neurodegenerative diseases such as Alzheimer's disease, and inflammasome inhibition rescues cognitive decline in rodent models of Alzheimer's disease. Here, we show that a dipeptide arising from the C9orf72 expansion, poly-glycine-arginine, activated the inflammasome in microglia and macrophages, leading to secretion of the pro-inflammatory cytokine, interleukin-1β. Poly-glycine-arginine also activated the inflammasome in organotypic hippocampal slice cultures, and immunofluorescence imaging demonstrated formation of inflammasome specks in response to poly-glycine-arginine. Several clinically available anti-inflammatory drugs rescued poly-glycine-arginine-induced inflammasome activation. These data suggest that C9orf72 dipeptides contribute to the neuroinflammation observed in patients, and highlight the inflammasome as a potential therapeutic target for frontotemporal dementia and amyotrophic lateral sclerosis.

Neuroprotective and Neurite Outgrowth Stimulating Effects of New Low-Basicity 5-HT7 Receptor Agonists: In Vitro Study in Human Neuroblastoma SH-SY5Y Cells

There is some evidence that the serotonin receptor subtype 7 (5-HT7) could be new therapeutic target for neuroprotection. The aim of this study was to compare the neuroprotective and neurite outgrowth potential of new 5-HT7 receptor agonists (AH-494, AGH-238, AGH-194) with 5-CT (5-carboxyamidotryptamine) in human neuroblastoma SH-SY5Y cells. The results revealed that 5-HT7 mRNA expression was significantly higher in retinoic acid (RA)-differentiated cells when compared to undifferentiated ones and it was higher in cell cultured in neuroblastoma experimental medium (DMEM) compared to those placed in neuronal (NB) medium. Furthermore, the safety profile of compounds was favorable for all tested compounds at concentration used for neuroprotection evaluation (up to 1 μM), whereas at higher concentrations (above 10 μM) the one of the tested compounds, AGH-194 appeared to be cytotoxic. While we observed relatively modest protective effects of 5-CT and AH-494 in UN-SH-SY5Y cells cultured in DMEM, in UN-SH-SY5Y cells cultured in NB medium we found a significant reduction of H2O2-evoked cell damage by all tested 5-HT7 agonists. However, 5-HT7-mediated neuroprotection was not associated with inhibition of caspase-3 activity and was not observed in RA-SH-SY5Y cells exposed to H2O2. Furthermore, none of the tested 5-HT7 agonists altered the damage induced by 6-hydroxydopamine (6-OHDA), 1-methyl-4-phenylpyridinium ion (MPP +) and doxorubicin (Dox) in UN- and RA-SH-SY5Y cells cultured in NB. Finally we showed a stimulating effect of AH-494 and AGH-194 on neurite outgrowth. The obtained results provide insight into neuroprotective and neurite outgrowth potential of new 5-HT7 agonists.

Redox Chemistry: Implications for Necrotizing Enterocolitis

Reduction-oxidation (redox) chemistry plays a vital role in human homeostasis. These reactions play critical roles in energy generation, as part of innate immunity, and in the generation of secondary messengers with various functions such as cell cycle progression or the release of neurotransmitters. Despite this cornerstone role, if left unchecked, the body can overproduce reactive oxygen species (ROS) or reactive nitrogen species (RNS). When these overwhelm endogenous antioxidant systems, oxidative stress (OS) occurs. In neonates, OS has been associated with retinopathy of prematurity (ROP), leukomalacia, and bronchopulmonary dysplasia (BPD). Given its broad spectrum of effects, research has started to examine whether OS plays a role in necrotizing enterocolitis (NEC). In this paper, we will discuss the basics of redox chemistry and how the human body keeps these in check. We will then discuss what happens when these go awry, focusing mostly on NEC in neonates.

Delineation of the role of G6PD in Alzheimer's disease and potential enhancement through microfluidic and nanoparticle approaches

Alzheimer's disease (AD) is a neurodegenerative pathologic entity characterized by the abnormal presence of tau and macromolecular Aβ deposition that leads to the degeneration or death of neurons. In addition to that, glucose-6-phosphate dehydrogenase (G6PD) has a multifaceted role in the process of AD development, where it can be used as both a marker and a target. G6PD activity is dysregulated due to its contribution to oxidative stress, neuroinflammation, and neuronal death. In this context, the current review presents a vivid depiction of recent findings on the relationship between AD progression and changes in the expression or activity of G6PD. The efficacy of the proposed G6PD-based therapeutics has been demonstrated in multiple studies using AD mouse models as representative animal model systems for cognitive decline and neurodegeneration associated with this disease. Innovative therapeutic insights are made for the boosting of G6PD activity via novel innovative nanotechnology and microfluidics tools in drug administration technology. Such approaches provide innovative methods of surpassing the blood-brain barrier, targeting step-by-step specific neural pathways, and overcoming biochemical disturbances that accompany AD. Using different nanoparticles loaded with G6DP to target specific organs, e.g., G6DP-loaded liposomes, enhances BBB penetration and brain distribution of G6DP. Many nanoparticles, which are used for different purposes, are briefly discussed in the paper. Such methods to mimic BBB on organs on-chip offer precise disease modeling and drug testing using microfluidic chips, requiring lower sample amounts and producing faster findings compared to conventional techniques. There are other contributions to microfluid in AD that are discussed briefly. However, there are some limitations accompanying microfluidics that need to be worked on to be used for AD. This study aims to bridge the gap in understanding AD with the synergistic use of promising technologies; microfluid and nanotechnology for future advancements.

Erythroid Differentiation Regulator 1 as a Regulator of Neuronal GSH Synthesis

Erythroid differentiation regulator 1 (Erdr1) is a cytokine known to play important roles in cell survival under stressful conditions, maintenance of cellular growth homeostasis, and activation of the immune system. However, the impact of Erdr1 on neurons remains undefined. In this study, we present novel evidence that Erdr1 plays a role in regulating glutathione (GSH) synthesis via glutamate transporter-associated protein 3-18 (GTRAP3-18), an anchor protein in the endoplasmic reticulum that holds excitatory amino acid carrier 1 (EAAC1) in neurons. Both DNA microarray and quantitative real-time PCR analyses revealed an approximately 2-fold increase in Erdr1 levels in the hippocampus of GTRAP3-18-deficient mice compared to those of wild-type mice. Knockdown of Erdr1 in vitro resulted in a decrease in GTRAP3-18 levels, leading to an increase in EAAC1 expression and intracellular GSH levels, and subsequently, cytoprotective effects against oxidative stress. Our findings shed light on the regulatory mechanisms involving Erdr1, GTRAP3-18, EAAC1, and GSH in the context of neuronal defense against oxidative stress. Understanding the intricate interplay among these molecules may pave the way for the development of promising therapeutic strategies for neurodegenerative disorders.

MALDI-mass spectrometry imaging as a new technique for detecting non-heme iron in peripheral tissues via caudal vein injection of deferoxamine

As one of the most common iron-chelating agents, deferoxamine (DFO) rapidly chelates iron in the body. Moreover, it does not compete for the iron characteristic of hemoglobin in the blood cells, which is common in the clinical treatment of iron poisoning. Iron is a trace element necessary to maintain organism normal life activities. Iron deficiency can lead to anemia, whereas iron overload can cause elevated levels of cellular oxidative stress and cell damage. As a consequence, detection of the iron content in tissues and blood is of great significance. The traditional techniques for detecting the iron content include inductively coupled plasma-mass spectrometry and atomic absorption spectrometry, which cannot be used for imaging purposes. Laser ablation-ICP-MS and synchrotron radiation micro-X-ray fluorescence can map the concentration and distribution of iron in tissues. However, these methods can only be used to measure the total iron levels in blood or tissues. In recent years, due to the deepening understanding of iron metabolism, diseases related to iron overload have attracted increasing attention. Therefore, we took advantage of the properties of DFO in terms of chelating iron and investigated different sampling times following DFO injection in the tail vein of mice. We used mass spectrometry imaging (MSI) technology to detect the DFO and ferrioxamine content in the blood and different tissues to indirectly characterize the non-heme iron content.

Physicochemistry, Nutritional, and Therapeutic Potential of Ficus carica - A Promising Nutraceutical

In an era where synthetic supplements have raised concerns regarding their effects on human health, Ficus carica has emerged as a natural alternative rich in polyphenolic compounds with potent therapeutic properties. Various studies on F. carica focusing on the analysis and validation of its pharmacological and nutritional properties are emerging. This paper summarizes present data and information on the phytochemical, nutritional values, therapeutic potential, as well as the toxicity profile of F. carica. An extensive search was conducted from various databases, including PubMed, ScienceDirect, Scopus, and Google Scholar. A total of 126 studies and articles related to F. carica that were published between 1999 and 2023 were included in this review. Remarkably, F. carica exhibits a diverse array of advantageous effects, including, but not limited to, antioxidant, anti-neurodegenerative, antimicrobial, antiviral, anti-inflammatory, anti-arthritic, antiepileptic, anticonvulsant, anti-hyperlipidemic, anti-angiogenic, antidiabetic, anti-cancer, and antimutagenic properties. Among the highlights include that antioxidants from F. carica were demonstrated to inhibit cholinesterase, potentially protecting neurons in Alzheimer's disease and other neurodegenerative conditions. The antimicrobial activities of F. carica were attributed to its high flavonoids and terpenoids content, while its virucidal action through the inhibition of DNA and RNA replication was postulated due to its triterpenes content. Inflammatory and arthritic conditions may also benefit from its anti-inflammatory and anti-arthritic properties through the modulation of various signalling proteins. Studies have also shown that F. carica extracts were generally safe and exhibit low toxicity profile, although more research in this aspect is required, specifically its effects on the skin. In conclusion, this study highlights the potential of F. carica as a valuable natural therapeutic agent and dietary supplement. However, continued exploration on F. carica's safety and efficacy is still required prior to embarking on clinical trials, as its role in personalized nutrition and medication will open a new paradigm to improve health outcomes.

Neurotoxicity of Some Environmental Pollutants to Zebrafish

The aquatic environment encompasses a wide variety of pollutants, from plastics to drug residues, pesticides, food compounds, and other food by-products, and improper disposal of waste is the main cause of the accumulation of toxic substances in water. Monitoring, assessing, and attempting to control the effects of contaminants in the aquatic environment are necessary and essential to protect the environment and thus human and animal health, and the study of aquatic ecotoxicology has become topical. In this respect, zebrafish are used as model organisms to study the bioaccumulation, toxicity, and influence of environmental pollutants due to their structural, functional, and material advantages. There are many similarities between the metabolism and physiological structures of zebrafish and humans, and the nervous system structure, blood-brain barrier function, and social behavior of zebrafish are characteristics that make them an ideal animal model for studying neurotoxicity. The aim of the study was to highlight the neurotoxicity of nanoplastics, microplastics, fipronil, deltamethrin, and rotenone and to highlight the main behavioral, histological, and oxidative status changes produced in zebrafish exposed to them.

Memantine Improves Memory and Neurochemical Damage in a Model of Maple Syrup Urine Disease

Maple Syrup Urine Disease (MSUD) is a metabolic disease characterized by the accumulation of branched-chain amino acids (BCAA) in different tissues due to a deficit in the branched-chain alpha-ketoacid dehydrogenase complex. The most common symptoms are poor feeding, psychomotor delay, and neurological damage. However, dietary therapy is not effective. Studies have demonstrated that memantine improves neurological damage in neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases. Therefore, we hypothesize that memantine, an NMDA receptor antagonist can ameliorate the effects elicited by BCAA in an MSUD animal model. For this, we organized the rats into four groups: control group (1), MSUD group (2), memantine group (3), and MSUD + memantine group (4). Animals were exposed to the MSUD model by the administration of BCAA (15.8 µL/g) (groups 2 and 4) or saline solution (0.9%) (groups 1 and 3) and treated with water or memantine (5 mg/kg) (groups 3 and 4). Our results showed that BCAA administration induced memory alterations, and changes in the levels of acetylcholine in the cerebral cortex. Furthermore, induction of oxidative damage and alterations in antioxidant enzyme activities along with an increase in pro-inflammatory cytokines were verified in the cerebral cortex. Thus, memantine treatment prevented the alterations in memory, acetylcholinesterase activity, 2',7'-Dichlorofluorescein oxidation, thiobarbituric acid reactive substances levels, sulfhydryl content, and inflammation. These findings suggest that memantine can improve the pathomechanisms observed in the MSUD model, and may improve oxidative stress, inflammation, and behavior alterations.

Panaxadiol carbamate derivatives: Synthesis and biological evaluation as potential multifunctional anti-Alzheimer agents

It is reported that panaxadiol has neuroprotective effects. Previous studies have found that compound with carbamate structure introduced at the 3-OH position of 20 (R) -panaxadiol showed the most effective neuroprotective activity with an EC50 of 13.17 μM. Therefore, we designed and synthesized a series of ginseng diol carbamate derivatives with ginseng diol as the lead compound, and tested their anti-AD activity. It was found that the protective effect of compound Q4 on adrenal pheochromocytoma was 80.6 ± 10.85 % (15 μM), and the EC50 was 4.32 μM. According to the ELISA results, Q4 reduced the expression of Aβ25-35 by decreasing β-secretase production. Molecular docking studies revealed that the binding affinity of Q4 to β-secretase was -49.67 kcal/mol, indicating a strong binding affinity of Q4 to β-secretase. Western blotting showed that compound Q4 decreased IL-1β levels, which may contribute to its anti-inflammatory effect. Furthermore, compound Q4 exhibits anti-AD activities by reducing abnormal phosphorylation of tau protein and activation of the mitogen activated protein kinase pathway. The learning and memory deficits in mice treated with Q4in vivo were significantly alleviated. Therefore, Q4 may be a promising multifunctional drug for the treatment of AD, providing a new way for anti-AD drugs.

Protective effect of Tat fused HPCA protein on neuronal cell death caused by ischemic injury

Background

Bain ischemia is a disease that occurs for various reasons, induces reactive oxygen species (ROS), and causes fatal damage to the nervous system. Protective effect of HPCA on ischemic injury has not been extensively studied despite its significance in regulating calcium homeostasis and promoting neuronal survival in CA1 region of the brain.

Objective

We investigate the role of HPCA in ischemic injury using a cell-permeable Tat peptide fused HPCA protein (Tat-HPCA).

Methods

Western blot analysis determined the penetration of Tat-HPCA into HT-22 cells and apoptotic signaling pathways. 5-CFDA, AM, DCF-DA, and TUNEL staining confirmed intracellular ROS production and DNA damage. The intracellular Ca2+ was measured in primary cultured neurons treated with H2O2. Protective effects were examined using immunohistochemistry and cognitive function tests by passive avoidance test and 8-arm radial maze test.

Results

Tat-HPCA effectively penetrated into HT-22 cells and inhibited H2O2-induced apoptosis, oxidative stress, and DNA fragmentation. It also effectively inhibited phosphorylation of JNK and regulated the activation of Caspase, Bax, Bcl-2, and PARP, leading to inhibition of apoptosis. Moreover, Ca2+ concentration decreased in cells treated with Tat-HPCA in primary cultured neurons. In an animal model of ischemia, Tat-HPCA effectively penetrated the hippocampus, inhibited cell death, and regulated activities of astrocytes and microglia. Additionally, Cognitive function tests show that Tat-HPCA improves neurobehavioral outcomes after cerebral ischemic injury.

Conclusion

These results suggest that Tat-HPCA might have potential as a therapeutic agent for treating oxidative stress-related diseases induced by ischemic injury, including ischemia.

Neuroprotective Role of Phytoconstituents-based Nanoemulsion for the Treatment of Alzheimer's Disease

Alzheimer's disease (AD) is the most prevalent form of neurodegenerative disorder (ND), affecting more than 44 million individuals globally as of 2023. It is characterized by cognitive dysfunction and an inability to perform daily activities. The progression of AD is associated with the accumulation of amyloid beta (Aβ), the formation of neurofibrillary tangles (NFT), increased oxidative stress, neuroinflammation, mitochondrial dysfunction, and endoplasmic reticulum stress. Presently, various phytomedicines and their bioactive compounds have been identified for their neuroprotective effects in reducing oxidative stress, alleviating neuroinflammation, and mitigating the accumulation of Aβ and acetylcholinesterase enzymes in the hippocampus and cerebral cortex regions of the brain. However, despite demonstrating promising anti-Alzheimer's effects, the clinical utilization of phytoconstituents remains limited in scope. The key factor contributing to this limitation is the challenges inherent in traditional drug delivery systems, which impede their effectiveness and efficiency. These difficulties encompass insufficient drug targeting, restricted drug solubility and stability, brief duration of action, and a lack of control over drug release. Consequently, these constraints result in diminished bioavailability and insufficient permeability across the blood-brain barrier (BBB). In response to these challenges, novel drug delivery systems (NDDS) founded on nanoformulations have emerged as a hopeful strategy to augment the bioavailability and BBB permeability of bioactive compounds with poor solubility. Among these systems, nanoemulsion (NE) have been extensively investigated for their potential in targeting AD. NE offers several advantages, such as ease of preparation, high drug loading, and high stability. Due to their nanosize droplets, NE also improves gut and BBB permeability leading to enhanced permeability of the drug in systemic circulation and the brain. Various studies have reported the testing of NE-based phytoconstituents and their bioactives in different animal species, including transgenic, Wistar, and Sprague-Dawley (SD) rats, as well as mice. However, transgenic mice are commonly employed in AD research to analyze the effects of Aβ. In this review, various aspects such as the neuroprotective role of various phytoconstituents, the challenges associated with conventional drug delivery, and the need for NDDS, particularly NE, are discussed. Various studies involving phytoconstituent-based NE for the treatment of AD are also discussed.

CCR5 deficiency: Decreased neuronal resilience to oxidative stress and increased risk of vascular dementia

INTRODUCTION

As the chemokine receptor5 (CCR5) may play a role in ischemia, we studied the links between CCR5 deficiency, the sensitivity of neurons to oxidative stress, and the development of dementia.

METHODS

Logistic regression models with CCR5/apolipoprotein E (ApoE) polymorphisms were applied on a sample of 205 cognitively normal individuals and 189 dementia patients from Geneva. The impact of oxidative stress on Ccr5 expression and cell death was assessed in mice neurons.

RESULTS

CCR5-Δ32 allele synergized with ApoEε4 as risk factor for dementia and specifically for dementia with a vascular component. We confirmed these results in an independent cohort from Italy (157 cognitively normal and 620 dementia). Carriers of the ApoEε4/CCR5-Δ32 genotype aged ≥80 years have an 11-fold greater risk of vascular-and-mixed dementia. Oxidative stress-induced cell death in Ccr5-/- mice neurons.

DISCUSSION

We propose the vulnerability of CCR5-deficient neurons in response to oxidative stress as possible mechanisms contributing to dementia.

Sesamol: A Phenolic Compound of Health Benefits and Therapeutic Promise in Neurodegenerative Diseases

Sesamol, one of the key bioactive ingredients of sesame seeds (Sesamum indicum L.), is responsible for many of its possible nutritional benefits. Both the Chinese and Indian medical systems have recognized the therapeutic potential of sesame seeds. It has been shown to have significant therapeutic potential against oxidative stress, inflammatory diseases, metabolic syndrome, neurodegeneration, and mental disorders. Sesamol is a benign molecule that inhibits the expression of inflammatory indicators like numerous enzymes responsible for inducing inflammation, protein kinases, cytokines, and redox status. This review summarises the potential beneficial effects of sesamol against neurological diseases including Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). Recently, sesamol has been shown to reduce amyloid peptide accumulation and attenuate cognitive deficits in AD models. Sesamol has also been demonstrated to reduce the severity of PD and HD in animal models by decreasing oxidative stress and inflammatory pathways. The mechanism of sesamol's pharmacological activities against neurodegenerative diseases will also be discussed in this review.

Potential Role of Oxidative Stress in the Pathophysiology of Neurodegenerative Disorders

Neurodegeneration causes premature death in the peripheral and central nervous system. Neurodegeneration leads to the accumulation of oxidative stress, inflammatory responses, and the generation of free radicals responsible for nervous disorders like amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and Huntington's disorders. Therefore, focus must be diverted towards treating and managing these disorders, as it is very challenging. Furthermore, effective therapies are also lacking, so the growing interest of the global market must be inclined towards developing newer therapeutic approaches that can intercept the progression of neurodegeneration. Emerging evidences of research findings suggest that antioxidant therapy has significant potential in modulating disease phenotypes. This makes them promising candidates for further investigation. This review focuses on the role of oxidative stress and reactive oxygen species in the pathological mechanisms of various neurodegenerative diseases, amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and Huntington's disorders and their neuroprotection. Additionally, it highlights the potential of antioxidant-based therapeutics in mitigating disease severity in humans and improving patient compliance. Ongoing extensive global research further sheds light on exploring new therapeutic targets for a deeper understanding of disease mechanisms in the field of medicine and biology targeting neurogenerative disorders.

Taste receptor type 1 member 3 mediates diet-induced cognitive impairment in mice

AIMS

Long-term consumption of a western diet (WD), which is characterized by high intake of saturated fats and sugary drinks, causes cognitive impairment. However, the molecular mechanism by which WD induces cognitive impairment remains unclear. Taste receptor type 1 member 3 (TAS1R3), activated by ligands of WD, is expressed in extra-oral tissues, including the brain, and particularly in the hippocampus. This study investigated whether TAS1R3 regulates WD-induced cognitive impairment in mice.

MAIN METHODS

Male C57BL/6J wild-type (WT) and Tas1r3 knock-out (KO) mice were fed either a normal diet (ND) or WD for 18 weeks. Cognitive functions were assessed using novel object recognition and Barnes maze tests. The mechanisms underlying WD-induced cognitive impairment were assessed using RNA-sequencing and bioinformatics analysis.

KEY FINDINGS

Cognitive impairment was observed in WT mice fed WD (WT-WD) compared with WT-ND mice. Conversely, mice lacking TAS1R3 were not cognitively impaired even under long-term WD feeding. Hippocampal transcriptome analysis revealed upregulated AMP-activated protein kinase (AMPK) signaling and increased AMPK-targeted sirtuin 3 expression in KO-WD mice. Pathway enrichment analysis showed that response to oxidative stress was downregulated, whereas neurogenesis was upregulated in dentate gyrus of KO-WD mice. In vitro studies validated the findings, indicating that Tas1r3 knockdown directly upregulated decreased sirtuin 3 expression, its downstream genes-related to oxidative stress, and apoptosis induced by WD condition in hippocampal neuron cells.

SIGNIFICANCE

TAS1R3 acts as a critical mediator of WD-induced cognitive impairment in mice, thereby offering potential as a novel therapeutic target to prevent WD-induced cognitive impairment.

CDNF overexpression prevents motor-cognitive dysfunction by intrastriatal CPP-based delivery system in a Parkinson's disease animal model

Parkinson's disease (PD) is characterized by the loss of dopaminergic neurons in the substantia nigra pars compact (SNpc), and no effective treatment has yet been established to prevent PD. Neurotrophic factors, such as cerebral dopamine neurotrophic factor (CDNF), have shown a neuroprotective effect on dopaminergic neurons. Previously, we developed a cell-penetrating-peptide-based delivery system that includes Asn194Lys mutation in the rabies virus glycoprotein-9R peptide (mRVG9R), which demonstrated a higher delivery rate than the wild-type. In this study, using a mouse PD-like model, we evaluated the intrastriatal mRVG9R-KP-CDNF gene therapy through motor and cognitive tests and brain cell analysis. The mRVG9R-KP-CDNF complex was injected into the striatum on days 0 and 20. To induce the PD-like model, mice were intraperitoneally administered Paraquat (PQ) twice a week for 6 weeks. Our findings demonstrate that mRVG9R-KP-CDNF gene therapy effectively protects brain cells from PQ toxicity and prevents motor and cognitive dysfunction in mice. We propose that the mRVG9R-KP-CDNF complex inhibits astrogliosis and microglia activation, safeguarding dopaminergic neurons and oligodendrocytes from PQ-induced damage. This study presents an efficient CDNF delivery system, protecting neurons and glia in the nigrostriatal pathway from PQ-induced damage, which is known to lead to motor and cognitive dysfunction in neurodegenerative diseases such as PD.

Catalytic antioxidant nanoparticles mitigate secondary injury progression and promote functional recovery in spinal cord injury model

Traumatic spinal cord injury exacerbates disability with time due to secondary injury cascade triggered largely by overproduction of reactive oxygen species (ROS) at the lesion site, causing oxidative stress. This study explored nanoparticles containing antioxidant enzymes (antioxidant NPs) to neutralize excess ROS at the lesion site and its impact. When tested in a rat contusion model of spinal cord injury, a single dose of antioxidant NPs, administered intravenously three hours after injury, effectively restored the redox balance at the lesion site, interrupting the secondary injury progression. This led to reduced spinal cord tissue inflammation, apoptosis, cavitation, and inhibition of syringomyelia. Moreover, the treatment reduced scar tissue forming collagen at the lesion site, protected axons from demyelination, and stimulated lesion healing, with further analysis indicating the formation of immature neurons. The ultimate effect of the treatment was improved motor and sensory functions and rapid post-injury weight loss recovery. Histological analysis revealed activated microglia in the spinal cord displaying rod-shaped anti-inflammatory and regenerative phenotype in treated animals, contrasting with amoeboid inflammatory and degenerative phenotype in untreated control. Overall data suggest that restoring redox balance at the lesion site shifts the dynamics in the injured spinal cord microenvironment from degenerative to regenerative, potentially by promoting endogenous repair mechanisms. Antioxidant NPs show promise to be developed as an early therapeutic intervention in stabilizing injured spinal cord for enhanced recovery.

Repurposing dimethyl fumarate as an antiepileptogenic and disease-modifying treatment for drug-resistant epilepsy

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.

Long-Term Effects of Perinatal Exposure to a Glyphosate-Based Herbicide on Melatonin Levels and Oxidative Brain Damage in Adult Male Rats

Concerns have been raised regarding the potential adverse health effects of the ubiquitous herbicide glyphosate. Here, we investigated long-term effects of developmental exposure to a glyphosate-based herbicide (GBH) by analyzing serum melatonin levels and cellular changes in the striatum of adult male rats (90 days old). Pregnant and lactating rats were exposed to 3% GBH (0.36% glyphosate) through drinking water from gestational day 5 to postnatal day 15. The offspring showed reduced serum melatonin levels (43%) at the adult age compared with the control group. The perinatal exposure to GBH also induced long-term oxidative stress-related changes in the striatum demonstrated by increased lipid peroxidation (45%) and DNA/RNA oxidation (39%) together with increased protein levels of the antioxidant enzymes, superoxide dismutase (SOD1, 24%), glutamate-cysteine ligase (GCLC, 58%), and glutathione peroxidase 1 (GPx1, 31%). Moreover, perinatal GBH exposure significantly increased the total number of neurons (20%) and tyrosine hydroxylase (TH)-positive neurons (38%) in the adult striatum. Mechanistic in vitro studies with primary rat pinealocytes exposed to 50 µM glyphosate demonstrated a decreased melatonin secretion partially through activation of metabotropic glutamate receptor 3 (mGluR3), while higher glyphosate levels (100 or 500 µM) also reduced the pinealocyte viability. Since decreased levels of the important antioxidant and neuroprotector melatonin have been associated with an increased risk of developing neurodegenerative disorders, this demonstrates the need to consider the melatonin hormone system as a central endocrine-related target of glyphosate and other environmental contaminants.

Oxytocin as neuro-hormone and neuro-regulator exert neuroprotective properties: A mechanistic graphical review

BACKGROUND

Neurodegeneration is progressive cell loss in specific neuronal populations, often resulting in clinical consequences with significant medical, societal, and economic implications. Because of its antioxidant, anti-inflammatory, and anti-apoptotic properties, oxytocin has been proposed as a potential neuroprotective and neurobehavioral therapeutic agent, including modulating mood disturbances and cognitive enchantment.

METHODS

Literature searches were conducted using the following databases Web of Science, PubMed, Elsevier Science Direct, Google Scholar, the Core Collection, and Cochrane from January 2000 to February 2023 for articles dealing with oxytocin neuroprotective properties in preventing or treating neurodegenerative disorders and diseases with a focus on oxidative stress, inflammation, and apoptosis/cell death.

RESULTS

The neuroprotective effects of oxytocin appears to be mediated by its anti-inflammatory properties, inhibition of neuro inflammation, activation of several antioxidant enzymes, inhibition of oxidative stress and free radical formation, activation of free radical scavengers, prevent of mitochondrial dysfunction, and inhibition of apoptosis.

CONCLUSION

Oxytocin acts as a neuroprotective agent by preventing neuro-apoptosis, neuro-inflammation, and neuronal oxidative stress, and by restoring mitochondrial function.

Reactive oxygen signaling molecule inducible regulation of CRISPR-Cas9 gene editing

We report development of a controllable gene editing tool that boronated gRNA, simply generated in situ, could regulate binding of gRNA molecules with either Cas9 endonuclease or target genes, thus serving as a modulator that can control CRISPR-Cas9 gene editing. Subsequent treatment with H2O2 facilitates the restoration of gene editing ability of the boronated gRNA to the level of using untreated gRNA. This is one of the few cases using small molecule to regulate CRISPR-Cas9 gene editing, which is a complement to the light approach, displaying great application potential. We develop a controllable gene editing tools based on the CRISPR-Cas9 gene editing system. This tool can be regulated by oxidative small molecule, i.e., H2O2. Compared with the light method, the application scope of our CRISPR-Cas9 systems have been widened with the small-molecule-triggered approaches, preventing the potential damage of cells or organism caused by UV light. In addition, the gain-of-function tools are expanding the gene code expansion for mechanistic studies of target enzymes since it provides a positive route to evaluate the activity of a given enzyme in dynamic and inversible regulation of targeting cellular processes.

Mechanisms of Microglia Proliferation in a Rat Model of Facial Nerve Anatomy

Although microglia exist as a minor glial cell type in the normal state of the brain, they increase in number in response to various disorders and insults. However, it remains unclear whether microglia proliferate in the affected area, and the mechanism of the proliferation has long attracted the attention of researchers. We analyzed microglial mitosis using a facial nerve transection model in which the blood-brain barrier is left unimpaired when the nerves are axotomized. Our results showed that the levels of macrophage colony-stimulating factor (M-CSF), cFms (the receptor for M-CSF), cyclin A/D, and proliferating cell nuclear antigen (PCNA) were increased in microglia in the axotomized facial nucleus (axotFN). In vitro experiments revealed that M-CSF induced cFms, cyclin A/D, and PCNA in microglia, suggesting that microglia proliferate in response to M-CSF in vivo. In addition, M-CSF caused the activation of c-Jun N-terminal kinase (JNK) and p38, and the specific inhibitors of JNK and p38 arrested the microglial mitosis. JNK and p38 were shown to play roles in the induction of cyclins/PCNA and cFms, respectively. cFms was suggested to be induced through a signaling cascade of p38-mitogen- and stress-activated kinase-1 (MSK1)-cAMP-responsive element binding protein (CREB) and/or p38-activating transcription factor 2 (ATF2). Microglia proliferating in the axotFN are anticipated to serve as neuroprotective cells by supplying neurotrophic factors and/or scavenging excite toxins and reactive oxygen radicals.

Peptide fraction from B. jararaca snake venom protects against oxidative stress-induced changes in neuronal PC12 cell but not in astrocyte-like C6 cell

Venom-derived proteins and peptides have prevented neuronal cell loss, damage, and death in the study of neurodegenerative disorders. The cytoprotective effects of the peptide fraction (PF) from Bothrops jararaca snake venom were evaluated against oxidative stress changes in neuronal PC12 cells and astrocyte-like C6 cells. PC12 and C6 cells were pre-treated for 4 h with different concentrations of PF, and then H2O2 was added (0.5 mM in PC12 cells; 0.4 mM in C6 cells) and incubated for 20 h more. In PC12 cells, PF at 0.78 μg mL-1 increased viability (113.6 ± 6.3%) and metabolism (96.3 ± 10.3%) cell against H2O2-induced neurotoxicity (75.6 ± 5.8%; 66.5 ± 3.3%, respectively), reducing oxidative stress markers such as ROS generation, NO production, and arginase indirect activity through urea synthesis. Despite that, PF showed no cytoprotective effects in C6 cells, but potentiated the H2O2-induced damage at a concentration lower than 0.07 μg mL-1. Furthermore, the role of metabolites derived from L-arginine metabolism was verified in PF-mediated neuroprotection in PC12 cells, using specific inhibitors of two of the key enzymes in the L-arginine metabolic pathway: the α-Methyl-DL-aspartic acid (MDLA) to argininosuccinate synthetase (AsS), responsible for the recycling of L-citrulline to L-arginine; and, L-NΩ-Nitroarginine methyl ester (L-Name) to nitric oxide synthase (NOS), which catalyzes the synthesis of NO from L-arginine. The inhibition of AsS and NOS suppressed PF-mediated cytoprotection against oxidative stress, indicating that its mechanism is dependent on the production pathway of L-arginine metabolites such as NO and, more importantly, polyamines from ornithine metabolism, which are involved in the neuroprotection mechanism described in the literature. Overall, this work provides novel opportunities for evaluating whether the neuroprotective properties of PF shown in particular neuronal cells are sustained and for exploring potential drug development pathways for the treatment of neurodegenerative diseases.

Pomegranate: A Source of Multifunctional Bioactive Compounds Potentially Beneficial in Alzheimer's Disease

Pomegranate fruit (PF) is a fruit rich in nutraceuticals. Nonedible parts of the fruit, especially peels, contain high amounts of bioactive components that have been largely used in traditional medicine, such as the Chinese, Unani, and Ayurvedic ones, for treating several diseases. Polyphenols such as anthocyanins, tannins, flavonoids, phenolic acids, and lignans are the major bioactive molecules present in PF. Therefore, PF is considered a source of natural multifunctional agents that exert simultaneously antioxidant, anti-inflammatory, antitumor, antidiabetic, cardiovascular, and neuroprotective activities. Recently, several studies have reported that the nutraceuticals contained in PF (seed, peel, and juice) have a potential beneficial role in Alzheimer's disease (AD). Research suggests that the neuroprotective effect of PF is mostly due to its potent antioxidant and anti-inflammatory activities which contribute to attenuate the neuroinflammation associated with AD. Despite the numerous works conducted on PF, to date the mechanism by which PF acts in combatting AD is not completely known. Here, we summarize all the recent findings (in vitro and in vivo studies) related to the positive effects that PF and its bioactive components can have in the neurodegeneration processes occurring during AD. Moreover, considering the high biotransformation characteristics of the nutraceuticals present in PF, we propose to consider the chemical structure of its active metabolites as a source of inspiration to design new molecules with the same beneficial effects but less prone to be affected by the metabolic degradation process.

Trends of mitochondrial changes in AD: a bibliometric study

Background

Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive progress and memory loss, which eventually develops into dementia. It can cause personality disorders and decreased quality of life of patients. Currently, AD patients account for 60-70% of global dementia patients and the incidence rate of AD is increasing annually. AD not only causes pain to patients but also brings a heavy burden to the entire family. Studies have found that there is a connection between mitochondrial dysfunction and other biochemical changes in AD like classical neuropathological hallmarks (β-amyloid and tau protein), inflammation pathways, oxidative stress, and so on. Evidence shows that early treatment targeted directly to mitochondria could extend the lifespan of model mice and decrease the relevant neuropathological markers. Therefore, research on the mitochondrial dysfunction of AD can be of potential significance for clinical treatment. To date, few bibliometric analysis articles related to mitochondrial dysfunction of AD have been published. Bibliometric analysis refers to quantitatively analyzing certain aspects of articles like publishers, authors, and countries by using statistical and mathematical methods. Combined with statistical software, a large number of papers can be converted to visualization figures and tables, which provide vital information such as keyword hotspots and the names of contributing authors. Through the bibliometric analysis method, our study aimed to provide study trends and keyword hotpots for researchers to conduct further relevant research in this field.

Methods

We used the Web of Science core collection database as a literature retrieval tool to obtain data related to mitochondrial changes in Alzheimer's disease during the last 20 years. The retrieval type was [TS = (Alzheimer's disease)] ND [TS = (mitochondrion)], ranging from January 1, 2000 to June 30, 2022. VOSviewer v1.6.18, Arcgis 10.8, and HistCite pro 2.1 were used to conduct data visualization analysis. VOSviewer v1.6.18 made relevant network visualization maps of the cooperative relationship between relevant countries, institutions, and authors (co-authorship), the frequency of different keywords appearing together (co-occurrence), and the frequency of different articles cited together (co-cited). Arcgis 10.8 created the world map of publications distribution in this field and Histcite pro 2.1 was used to count the local citation score (LCS) of references. In addition, Journal Citation Reports were used to consult the latest journal import factor and JCI quartile.

Results

As of June 30, 2022, from the Web of Science core collection, we selected 2,474 original articles in English, excluding the document types of the news items, meeting abstracts, and some articles that had little relevance to our theme. The United States acted as the leader and enjoyed a high reputation in this field. The University of California System was the institution that made the greatest contribution (3.64% with 90 papers). Most articles were published in the Journal of Alzheimer's Disease (8.21%, with 203 papers). The most frequently co-cited journal in Q1 was the Journal of Biological Chemistry (8,666 citations, TLS: 1039591). Russel H. Swerdlow (55 publications) was the most productive author and PH Reddy was the most co-cited author with 1,264 citations (TLS: 62971). The hotpots of mitochondrial dysfunction in AD were as follows: "oxidative stress," "amyloid-beta-protein," "tau," "apoptosis," "inflammation," "autophagy," "precursor protein," "endoplasmic-reticulum," "dynamics" and "mitochondrial unfolded protein response."

Conclusion

This bibliometric analysis research will help readers rapidly identify current hotpots and milestone studies related to directions of interest in AD research.

Engineering Single-Atom Nanozymes for Catalytic Biomedical Applications

Nanomaterials with enzyme-mimicking properties, coined as nanozymes, are a promising alternative to natural enzymes owing to their remarkable advantages, such as high stability, easy preparation, and favorable catalytic performance. Recently, with the rapid development of nanotechnology and characterization techniques, single atom nanozymes (SAzymes) with atomically dispersed active sites, well-defined electronic and geometric structures, tunable coordination environment, and maximum metal atom utilization are developed and exploited. With superior catalytic performance and selectivity, SAzymes have made impressive progress in biomedical applications and are expected to bridge the gap between artificial nanozymes and natural enzymes. Herein, the recent advances in SAzyme preparation methods, catalytic mechanisms, and biomedical applications are systematically summarized. Their biomedical applications in cancer therapy, oxidative stress cytoprotection, antibacterial therapy, and biosensing are discussed in depth. Furthermore, to appreciate these advances, the main challenges, and prospects for the future development of SAzymes are also outlined and highlighted in this review.

Effectiveness of coenzyme Q10 on learning and memory and synaptic plasticity impairment in an aged Aβ-induced rat model of Alzheimer's disease: a behavioral, biochemical, and electrophysiological study

RATIONALE

Aging is the major risk factor for Alzheimer's disease (AD), and cognitive and memory impairments are common among the elderly. Interestingly, coenzyme Q10 (Q10) levels decline in the brain of aging animals. Q10 is a substantial antioxidant substance, which has an important role in the mitochondria.

OBJECTIVE

We assessed the possible effects of Q10 on learning and memory and synaptic plasticity in aged β-amyloid (Aβ)-induced AD rats.

METHODS

In this study, 40 Wistar rats (24-36 months old; 360-450 g) were randomly assigned to four groups (n = 10 rats/group)-group I: control, group II: Aβ, group III: Q10; 50 mg/kg, and group IV: Q10+Aβ. Q10 was administered orally by gavage daily for 4 weeks before the Aβ injection. The cognitive function and learning and memory of the rats were measured by the novel object recognition (NOR), Morris water maze (MWM), and passive avoidance learning (PAL) tests. Finally, malondialdehyde (MDA), total antioxidant capacity (TAC), total thiol group (TTG), and total oxidant status (TOS) were measured.

RESULTS

Q10 improved the Aβ-related decrease in the discrimination index in the NOR test, spatial learning and memory in the MWM test, passive avoidance learning and memory in the PAL test, and long-term potentiation (LTP) impairment in the hippocampal PP-DG pathway in aged rats. In addition, Aβ injection significantly increased serum MDA and TOS levels. Q10, however, significantly reversed these parameters and also increased TAC and TTG levels in the Aβ+Q10 group.

CONCLUSIONS

Our experimental findings suggest that Q10 supplementation can suppress the progression of neurodegeneration that otherwise impairs learning and memory and reduces synaptic plasticity in our experimental animals. Therefore, similar supplemental Q10 treatment given to humans with AD could possibly provide them a better quality of life.

Structure modification: a successful tool for prodrug design

Prodrug strategy is critical for innovative drug development. Structural modification is the most straightforward and effective method to develop prodrugs. Improving drug defects and optimizing the physical and chemical properties of a drug, such as lipophilicity and water solubility, changing the way of administration can be achieved through specific structural modification. Designing prodrugs by linking microenvironment-responsive groups to the prototype drugs is of great help in enhancing drug targeting. In the meantime, making connections between prodrugs and suitable drug delivery systems could realize drug loading increases, greater stability, bioavailability and drug release control. In this paper, lipidic, water-soluble, pH-responsive, redox-sensitive and enzyme-activatable prodrugs are reviewed on the basis of structural modification.

Ketogenic Diet as a Promising Non-Drug Intervention for Alzheimer’s Disease: Mechanisms and Clinical Implications

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that is mainly characterized by cognitive deficits. Although many studies have been devoted to developing disease-modifying therapies, there has been no effective therapy until now. However, dietary interventions may be a potential strategy to treat AD. The ketogenic diet (KD) is a high-fat and low-carbohydrate diet with adequate protein. KD increases the levels of ketone bodies, providing an alternative energy source when there is not sufficient energy supply because of impaired glucose metabolism. Accumulating preclinical and clinical studies have shown that a KD is beneficial to AD. The potential underlying mechanisms include improved mitochondrial function, optimization of gut microbiota composition, and reduced neuroinflammation and oxidative stress. The review provides an update on clinical and preclinical research on the effects of KD or medium-chain triglyceride supplementation on symptoms and pathophysiology in AD. We also detail the potential mechanisms of KD, involving amyloid and tau proteins, neuroinflammation, gut microbiota, oxidative stress, and brain metabolism. We aimed to determine the function of the KD in AD and outline important aspects of the mechanism, providing a reference for the implementation of the KD as a potential therapeutic strategy for AD.

Fluoride Induced Neurobehavioral Impairments in Experimental Animals: a Brief Review

Fluoride is one of the major toxicants in the environment and is often found in drinking water at higher concentrations. Living organisms including humans exposed to high fluoride levels are found to develop mild-to-severe detrimental pathological conditions called fluorosis. Fluoride can cross the hematoencephalic barrier and settle in various brain regions. This accumulation affects the structure and function of both the central and peripheral nervous systems. The neural ultrastructure damages are reflected in metabolic and cognitive activities. Hindrances in synaptic plasticity and signal transmission, early neuronal apoptosis, functional alterations of the intercellular signaling pathway components, improper protein synthesis, dyshomeostasis of the transcriptional and neurotrophic factors, oxidative stress, and inflammatory responses are accounted for the fluoride neurotoxicity. Fluoride causes a decline in brain functions that directly influence the overall quality of life in both humans and animals. Animal studies are widely used to explore the etiology of fluoride-induced neurotoxicity. A good number of these studies support a positive correlation between fluoride intake and toxicity phenotypes closely associated with neurotoxicity. However, the experimental dosages highly surpass the normal environmental concentrations and are difficult to compare with human exposures. The treatment procedures are highly dependent on the dosage, duration of exposure, sex, and age of specimens among other factors which make it difficult to arrive at general conclusions. Our review aims to explore fluoride-induced neuronal damage along with associated histopathological, behavioral, and cognitive effects in experimental models. Furthermore, the correlation of various molecular mechanisms upon fluoride intoxication and associated neurobehavioral deficits has been discussed. Since there is no well-established mechanism to prevent fluorosis, phytochemical-based alleviation of its characteristic indications has been proposed as a possible remedial measure.

Antioxidant and Antineuroinflammatory Mechanisms of Kaempferol-3-O-β-d-Glucuronate on Lipopolysaccharide-Stimulated BV2 Microglial Cells through the Nrf2/HO-1 Signaling Cascade and MAPK/NF-κB Pathway

Aglycone- and glycoside-derived forms of flavonoids exist broadly in plants and foods such as fruits, vegetables, and peanuts. However, most studies focus on the bioavailability of flavonoid aglycone rather than its glycosylated form. Kaempferol-3-O-β-d-glucuronate (K3G) is a natural flavonoid glycoside obtained from various plants that have several biological activities, including antioxidant and anti-inflammatory effects. However, the molecular mechanism related to the antioxidant and antineuroinflammatory activity of K3G has not yet been demonstrated. The present study was designed to demonstrate the antioxidant and antineuroinflammatory effect of K3G against lipopolysaccharide (LPS)-stimulated BV2 microglial cells and to evaluate the underlying mechanism. Cell viability was determined by MTT assay. The inhibition rate of reactive oxygen species (ROS) and the production of pro-inflammatory mediators and cytokines were measured by DCF-DA assay, Griess assay, enzyme-linked immunosorbent assay (ELISA), and western blotting. K3G inhibited the LPS-induced release of nitric oxide, interleukin (IL)-6, and tumor necrosis factor-α (TNF-α) as well as the expression of prostaglandin E synthase 2. Additionally, K3G reduced the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor-kappa B (NF-κB) related proteins. Mechanistic studies found that K3G downregulated phosphorylated mitogen-activated protein kinases (MAPKs) and upregulated the Nrf2/HO-1 signaling cascade. In this study, we demonstrated the effects of K3G on antineuroinflammation by inactivating phosphorylation of MPAKs and on antioxidants by upregulating the Nrf2/HO-1 signaling pathway through decreasing ROS in LPS-stimulated BV2 cells.