Brain Levels Research Articles

Japanese encephalitis virus-induced DNA methylation contributes to blood-brain barrier permeability by modulating tight junction protein expression

Japanese encephalitis virus (JEV) is a neurotropic and neuroinvasive flavivirus causing viral encephalitis, which seriously threatens the development of animal husbandry and human health. DNA methylation is a major epigenetic modification involved in viral pathogenesis, yet how DNA methylation affects JEV infection remains unknown. Here, we show genome-wide DNA methylation profiles in the brains of JEV-infected mice compared to mock-infected mice. JEV can significantly increase the overall DNA methylation levels in JEV-infected mouse brains. A total of 14,781 differentially methylated regions associated genes (DMGs) have been identified. Subsequently, KEGG pathway analysis suggested that DNA methylation modulates the tight junction signaling pathway, which can potentially impact the permeability of the blood-brain barrier (BBB). We demonstrate that hypermethylation of the tight junction gene Afdn promoter inhibited AFDN expression and increased monolayer permeability of mouse brain microvascular endothelial (bEnd.3) cells in an in vitro transwell assay. Collectively, this study reveals that DNA methylation is increased in a murine Japanese encephalitis model and that modulation of Afdn expression promotes BBB permeability.

Neuroprotective Roles of Lauric Acid and Resveratrol: Shared Benefits in Neuroinflammation and Anxiety, Distinct Effects on Memory Enhancement

ABSTRACTNeuroinflammation can be triggered by a high‐fat/high‐fructose diet (HFFD), and CD36 may be an underlying mechanism. Lauric acid (LA), the major fatty acid in coconut oil, and resveratrol, the plant‐based polyphenolic compound, may exert anti‐inflammatory effects. Therefore, this study investigated the possible effects of LA and resveratrol on diet‐induced neuroinflammation and CD36. Healthy male C57BL/6 mice (8 weeks of age, n = 31) were fed a control diet (10%kcal fat) or diets containing high fat (60%kcal fat) and fructose (5% w/v fructose drinking water) for 6 weeks, ad libitum. Supplemented to the HFFD, mice daily received resveratrol (7.5 mg/kg) (HFFD‐RSV) or LA (750 mg/kg) (HFFD‐LA). At the end of the study, HFFD resulted in anxiety‐like behavior, reduced locomotor activity, neuroinflammation (increased brain GFAP, IL‐6, MCP‐1, IFN‐γ, TNF‐α), and systemic inflammation (increased plasma GFAP, IFN‐γ, TNF‐α, IL‐12p70, reduced plasma IL‐10). HFFD‐RSV and HFFD‐LA alleviated HFFD‐induced anxiety‐like behavior, neuroinflammation, and systemic inflammation. HFFD‐LA improved memory. Brain and plasma CD36 levels were increased by HFFD and reduced by HFFD‐RSV or HFFD‐LA. Dietary resveratrol and LA intake may alleviate HFFD‐induced neuroinflammation, systemic inflammation, and anxiety‐like behavior and improve memory, as CD36 may be an underlying mechanism.

Element Changes Occurring in Brain Point at the White Matter Abnormalities in Rats Exposed to the Ketogenic Diet During Prenatal Life.

A large number of clinical studies demonstrate that the ketogenic diet (KD) may be an effective approach to the reduction of epileptic seizures in children and adults. Such dietary therapy could also help pregnant women with epilepsy, especially since most antiseizure drugs have teratogenic action. However, there is a lack of medical data, considering the safety of using KD during gestation for the progeny. Therefore, we examined the influence of KD used prenatally in rats on the elemental composition of the selected brain regions in their offspring. For this purpose, synchrotron radiation-induced X-ray fluorescence (SR-XRF) microscopy was utilized, and elements such as P, S, K, Ca, Fe, and Zn were determined. Moreover, to verify whether the possible effects of KD are temporary or long-term, different stages of animal postnatal development were taken into account in our experiment. The obtained results confirmed the great applicability of SR-XRF microscopy to track the element changes occurring in the brain during postnatal development as well as those induced by prenatal exposure to the high-fat diet. The topographic analysis of the brains taken from offspring of mothers fed with KD during pregnancy and appropriate control individuals showed a potential influence of such dietary treatment on the brain levels of elements such as P and S. In the oldest progeny, a significant reduction of the surface of brain areas characterized by an increased P and S content, which histologically/morphologically correspond to white matter structures, was noticed. In turn, quantitative elemental analysis showed significantly decreased levels of Fe in the striatum and white matter of 30-day-old rats exposed prenatally to KD. This effect was temporary and was not noticed in adult animals. The observed abnormalities may be related to the changes in the accumulation of sphingomyelin and sulfatides and may testify about disturbances in the structure and integrity of the myelin, present in the white matter.

Neuronal SLC39A8 deficiency impairs cerebellar development by altering manganese homeostasis.

Solute carrier family 39, member 8 (SLC39A8), is a transmembrane transporter that mediates the cellular uptake of zinc, iron, and manganese (Mn). Human genetic studies document the involvement of SLC39A8 in Mn homeostasis, brain development, and function. However, the role and pathophysiological mechanisms of SLC39A8 in the central nervous system remain elusive. We generated Slc39a8 neuron-specific knockout (Slc39a8-NSKO) mice to study SLC39A8 function in neurons. The Slc39a8-NSKO mice displayed markedly decreased Mn levels in the whole brain and brain regions, especially the cerebellum. Radiotracer studies using 54Mn revealed that Slc39a8-NSKO mice had impaired brain uptake of Mn. Slc39a8-NSKO cerebellums exhibited morphological defects and abnormal dendritic arborization of Purkinje cells. Reduced neurogenesis and increased apoptotic cell death occurred in the cerebellar external granular layer of Slc39a8-NSKO mice. Brain Mn deficiency in Slc39a8-NSKO mice was associated with motor dysfunction. Unbiased RNA-Seq analysis revealed downregulation of key pathways relevant to neurodevelopment and synaptic plasticity, including cAMP signaling pathway genes. We further demonstrated that Slc39a8 was required for the optimal transcriptional response to the cAMP-mediated signaling pathway. In summary, our study highlighted the essential roles of SLC39A8 in brain Mn uptake and cerebellum development and functions.

Limosilactobacillus-related 3-OMDP as a potential therapeutic target for depression

Objective Gut microbiota was closely involved in the pathogenesis of depression, but the underlying molecular mechanisms in depression remained unclear. This study was conducted to investigate the relationship between neurotransmitters/inflammatory factors and gut microbiota in depressed mice. Materials and methods A chronic social defeat stress (CSDS) depression model was established. Gut microbial composition was detected in faeces, neurotransmitters were detected in faeces, colon, blood and hippocampus, and inflammatory factors were detected in hippocampus. After a key neurotransmitter was identified, intervention experiment was conducted to explore whether it could improve depressive-like behaviours. Results Six differential genera in faeces, 14 differential neurotransmitters in gut-brain axis, and two differential inflammatory factors (interleukin-1 beta (IL-1β) and interleukin-6 (IL-6)) in hippocampus were identified in depressed mice. There were significant correlations among differential genera, differential neurotransmitters and IL-1β/IL-6. Among these differential neurotransmitters, 3-O-Methyldopa (3-OMDP) was found to be consistently decreased in faeces, colon, blood and hippocampus, and 3-OMDP was significantly correlated to Limosilactobacillus and IL-1β. After receiving 3-OMDP, the depressive-like behaviours in depressed mice were improved and the increased IL-1β/IL-6 levels were reversed. Conclusions These results indicated that gut microbiota might affect host’s inflammation levels in brain through regulating neurotransmitters, eventually leading to the onset of depression. ‘Limosilactobacillus-3-OMDP-IL-1β/IL-6’ might be a potential pathway in the crosstalk of gut and brain, and 3-OMDP held the promise as a therapeutic target for depression.

Immunomodulatory effect of bovine lactoferrin during SARS-CoV-2 infection

IntroductionLactoferrin (Lf) is an important immunomodulator in infections caused by different agents. During SARS-CoV-2 infection, Lf can hinder or prevent virus access to the intracellular environment. Severe cases of COVID-19 are related to increased production of cytokines, accompanied by a weak type 1 interferon response.MethodsWe investigated the influence of bovine Lf (bLf) in the immune response during SARS-CoV-2 infection in vitro and in vivo assays.ResultsOur results show a strong binding between bLf and TLR4/NF-κB in silico, as well as an increase in mRNA expression of these genes in peripheral blood mononuclear cells (PBMCs) treated with bLf. Furthermore, the treatment increased TLR4/TLR9 mRNA expression in infected K18-hACE2 mouse blood, indicating an activation of innate response. Our results show that, when bLf was added, a reduction in the NK cell population was found, presenting a similar effect on PD-1 in TCD4+ and TCD8+ cells. In the culture supernatant of PBMCs from healthy participants, bLf decreased IL-6 levels and increased CCL5 in COVID-19 participants. In addition, K18-hACE2 mice infected and treated with bLf presented an increase of serum pro-inflammatory markers (GM-CSF/IL-1β/IL-2) and upregulated mRNA expression of IL1B and IL6 in the lung tissue. Furthermore, bLf treatment was able to restore FTH1 levels in brain tissue.DiscussionThe data indicate that bLf can be part of a therapeutic strategy to promote the immunomodulation effect, leading to homeostasis during COVID-19.

Conversion of 5α-Androstane-3α,17β-diol to bis[(4-dimethylamino)phenyl carbamate] derivative for sensitive determination of its rat brain level by LC/ESI-MS/MS.

5α-Androstane-3α,17β-diol (3α,5α-Adiol) is a testosterone-derived neurosteroid and has anxiolytic and analgesic effects via γ-aminobutyric acid type A receptors as with the progesterone-derived neurosteroid, allopregnanolone (AP). Although the psychotropic drug-evoked changes in the brain AP concentration have been intensively studied, those in the brain 3α,5α-Adiol concentration remain poorly understood. One of the causes for this is the limited availability of a validated method for quantifying the brain 3α,5α-Adiol with a sufficient sensitivity and specificity, which is described in this study. To enhance the detectability of 3α,5α-Adiol by electrospray ionization-tandem mass spectrometry (ESI-MS/MS), derivatization with 4-dimethylaminobenzoyl azide was employed. The brain sample was purified by solid-phase extraction and the recovered 3α,5α-Adiol and the deuterated internal standard were derivatized, then measured by liquid chromatography (LC)/ESI-MS/MS with selected reaction monitoring. The derivatized 3α,5α-Adiol, i.e., the bis[(4-dimethylamino)phenyl carbamate] derivative, provided the intense doubly-protonated molecule as the precursor ion, then the specific product ion containing the 3α,5α-Adiol-skeleton by collision-induced dissociation. The detectability of 3α,5α-Adiol was eventually increased 1000-fold by derivatization. Separation of the derivatized 3α,5α-Adiol from its stereoisomers and interfering brain components was achieved using a SunShell Biphenyl column with an isopropyl alcohol-containing mobile phase. A good linearity in the sufficient concentration range, acceptable precision and accuracy, and negligible matrix effect were demonstrated by the validation tests. The animal (rat) study using this method revealed that the brain 3α,5α-Adiol levels were unaffected by the administration of fluoxetine (FLX) and clozapine (CLZ), in contrast to the significant increase of the AP levels. An LC/ESI-MS/MS method capable of quantifying 3α,5α-Adiol in the rat brain using a 20-mg tissue was developed and validated. The brain levels of 3α,5α-Adiol had an entirely different behavior from those of AP due to FLX and CLZ administration.

Diaminonaphthalene Boronic Acid (DANBA): New Approach for Peroxynitrite Sensing Site

AbstractSelective detection of reactive oxygen species (ROS) is vital for studying their role in brain diseases. Fluorescence probes can distinguish ONOO− species from other ROS; however, their selectivity toward ONOO− species depends on the ONOO− recognition group. Aryl‐boronic acids and esters, which are common ONOO− recognition groups, are not selective for ONOO− over H2O2. In this study, we developed a diaminonaphthalene (DAN)‐protected boronic acid as a new ONOO− recognition group that selectively reacts with ONOO− over H2O2 and other ROS. Three DAN‐protected boronic acid (DANBA)‐based fluorophores that emit fluorescence over visible to near‐infrared (NIR) regions, Cou‐BN, BVP‐BN, and HDM‐BN, and their aryl‐boronic acid‐based counterparts (Cou‐BO, BVP‐BO, and HDM‐BO), were developed. The DANBA‐based probes exhibited enhanced selectivity toward ONOO− over that of their control group, as well as universality in solution assays and in vitro experiments with PC12 cells. The NIR‐emissive HDM‐BN was optimized to delineate in vivo ONOO− levels in mouse brains with Parkinson's disease. This DAN‐protected boronic acid belongs to a new generation of recognition groups for developing ONOO− probes, and this strategy could be extended to other common hydroxyl‐containing dyes to detect ONOO− levels in complex biological systems and processes.

Diaminonaphthalene Boronic Acid (DANBA): New Approach for Peroxynitrite Sensing Site.

Selective detection of reactive oxygen species (ROS) is vital for studying their role in brain diseases. Fluorescence probes can distinguish ONOO- species from other ROS; however, their selectivity toward ONOO- species depends on the ONOO- recognition group. Aryl-boronic acids and esters, which are common ONOO- recognition groups, are not selective for ONOO- over H2O2. In this study, we developed a diaminonaphthalene (DAN)-protected boronic acid as a new ONOO- recognition group that selectively reacts with ONOO- over H2O2 and other ROS. Three DAN-protected boronic acid (DANBA)-based fluorophores that emit fluorescence over visible to near-infrared (NIR) regions, Cou-BN, BVP-BN, and HDM-BN, and their aryl-boronic acid-based counterparts (Cou-BO, BVP-BO, and HDM-BO), were developed. The DANBA-based probes exhibited enhanced selectivity toward ONOO- over that of their control group, as well as universality in solution assays and in vitro experiments with PC12 cells. The NIR-emissive HDM-BN was optimized to delineate in vivo ONOO- levels in mouse brains with Parkinson's disease. This DAN-protected boronic acid belongs to a new generation of recognition groups for developing ONOO- probes, and this strategy could be extended to other common hydroxyl-containing dyes to detect ONOO- levels in complex biological systems and processes.

Herniarin ameliorates acrylamide-induced neurotoxicity in rat: involvement of neuro-inflammation and acetylcholinesterase

This study aimed to investigate the protective effects of herniarin against acrylamide neuro-toxicity. Rats were administered 50 mg/kg of acrylamide (Acr) along with oral doses of herniarin at 50, 100, and 200 mg/kg for 11 days. After treatment, the animals were sacrificed and biochemical markers including superoxide dismutase (SOD), catalase activity, malondialdehyde (MDA), nitric oxide (NO), thiols and acetylcholine esterase (AChE) level were evaluated. Moreover, mRNA expression of neuro-inflammatory cytokines including TNF-α, IL-1β, and IL-6 were measured using qRT-PCR method. As results, Acr increased MDA with subsequent reduction in SOD, catalase, and thiols content. In contrast, administration of herniarin remarkably normalised the antioxidants and decreased lipid peroxidation. Furthermore, it downregulated mRNA expression of TNF-α, IL-1β, and IL-6 (p < 0.001) as well as decreased NO (p < 0.01) and AchE levels (p < 0.001) in the Acr-injured brains. Herniarin ameliorated Acr-induced brain injury via modulating redox hemostasis, cholinergic function, as well as inhibiting neuro-inflammation in rats.

Locomotor and gait changes in the LPS model of neuroinflammation are correlated with inflammatory cytokines in blood and brain.

Lipopolysaccharide (LPS) challenge in mice has been used to identify the mechanisms and therapeutics for neuroinflammation. In this study, we aimed to comprehensively evaluate the behavioral changes including locomotion, exploration, and memory, correlating them with a panel of thirteen inflammatory cytokines in both blood and brain.We found that acute LPS administration (0.83 mg/Kg i.p.) reduced body weight, food intake, and glucose levels compared to the saline-injected mice, concomitant with decreased activity in home cage monitoring. Locomotion was significantly reduced in Open Field, Introduced Object, and Y-Maze tests. Decreased exploratory behavior in the Y-Maze and Introduced Object tests was noticed, by measuring the number of arms explored and object interaction time, respectively. Additionally, in rotarod, LPS administration led to a significant decrease in the distance achieved, while in the MouseWalker, LPS led to a reduction in average velocity.LPS induced a decrease in microglia ramification index in the motor cortex and the striatum, while surprisingly a reduction in microglia number was observed in the motor cortex.The concentrations of thirteen cytokines in the blood were significantly altered, while only CXCL1, CCL22, CCL17, G-CSF, and IL-12p40 were changed in the brain. Correlations between cytokine levels in blood and brain were found, most notably for CCL17 and CCL22. TGFβ was the only one with negative correlations to other cytokines. Correlations between cytokines and behavior changes were also disclosed, especially for CCL17, CCL22, G-CSF, and IL-6 and negatively for TGFβ and IL-10.In summary, our study employing acute LPS challenge in mice has revealed a comprehensive profile of behavioral alterations alongside significant changes in inflammatory cytokine levels, both in peripheral blood and brain tissue. These findings contribute to a deeper understanding of the interplay between inflammation and behavior, with possible implications for identifying prognostics and therapeutic targets for neuroinflammatory conditions.

Medial prefrontal cortex acetylcholine signaling mediates the ability to learn an active avoidance response following learned helplessness training.

Increased brain levels of acetylcholine (ACh) have been observed in patients with depression, and increasing ACh levels pharmacologically can precipitate stress-related behaviors in humans and animals. Conversely, optimal ACh levels are required for cognition and memory. We hypothesize that excessive ACh signaling results in strengthening of negative encoding in which memory formation is aberrantly strengthened for stressful events. The medial prefrontal cortex (mPFC) is critical for both top-down control of stress-related circuits, and for encoding of sensory experiences. We therefore evaluated the role of ACh signaling in the mPFC in a learned helplessness task in which mice were exposed to repeated inescapable stressors followed by an active avoidance task. Using fiber photometry with a genetically-encoded ACh sensor, we found that ACh levels in the mPFC during exposure to inescapable stressors were positively correlated with later escape deficits in an active avoidance test in males, but not females. Consistent with these measurements, we found that both pharmacologically- and chemogenetically-induced increases in mPFC ACh levels resulted in escape deficits in both male and female mice, whereas chemogenetic inhibition of ACh neurons projecting to the mPFC improved escape performance in males, but impaired escape performance in females. These results highlight the adaptive role of ACh release in stress response, but also support the idea that sustained elevation of ACh contributes to maladaptive behaviors. Furthermore, mPFC ACh signaling may contribute to stress-based learning differentially in males and females.

Hepatocyte activation and liver injury following cerebral ischemia promote HMGB1-mediated hepcidin upregulation in hepatocytes and regulation of systemic iron levels.

We previously reported that high mobility group box 1 (HMGB1), a danger-associated molecular pattern (DAMP), increases intracellular iron levels in the postischemic brain by upregulating hepcidin, a key regulator of iron homeostasis, triggering ferroptosis. Since hepatocytes are the primary cells that produce hepcidin and control systemic iron levels, we investigated whether cerebral ischemia induces hepcidin upregulation in hepatocytes. Following middle cerebral artery occlusion (MCAO) in a rodent model, significant liver injury was observed. This injury was evidenced by significantly elevated Eckhoff's scores and increased serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Additionally, total iron levels were significantly elevated in the liver, with intracellular iron accumulation detected in hepatocytes. Hepcidin expression in the liver, which is primarily localized in hepatocytes, increased significantly starting at 3 h after MCAO and continued to increase rapidly, reaching a peak at 24 h. Interestingly, HMGB1 levels in the liver were also significantly elevated after MCAO, with the disulfide form of HMGB1 being the major subtype. In vitro experiments using AML12 hepatocytes showed that recombinant disulfide HMGB1 significantly upregulated hepcidin expression in a Toll-like receptor 4 (TLR4)- and RAGE-dependent manner. Furthermore, treatment with a ROS scavenger and a peptide HMGB1 antagonist revealed that both ROS generation and HMGB1 induction contributed to hepatocyte activation and liver damage following MCAO-reperfusion. In conclusion, this study revealed that cerebral ischemia triggers hepatocyte activation and liver injury. HMGB1 potently induces hepcidin not only in the brain but also in the liver, thereby influencing systemic iron homeostasis following ischemic stroke.

Distinct regional vulnerability to Aβ and iron accumulation in post mortem AD brains.

The paramagnetic iron, diamagnetic amyloid beta (Aβ) plaques and their interaction are crucial in Alzheimer's disease (AD) pathogenesis, complicating non-invasive magnetic resonance imaging for prodromal AD detection. We used a state-of-the-art sub-voxel quantitative susceptibility mapping method to simultaneously measure Aβ and iron levels in post mortem human brains, validated by histology. Further transcriptomic analysis using Allen Human Brain Atlas elucidated the underlying biological processes. Regional increased paramagnetic and diamagnetic susceptibility were observed in medial prefrontal, medial parietal, and para-hippocampal cortices associated with iron deposition (R=0.836, p=0.003) and Aβ accumulation (R=0.853, p=0.002) in AD brains. Higher levels of gene expression relating to cell cycle, post-translational protein modifications, and cellular response to stress were observed. These findings provide quantitative insights into the variable vulnerability of cortical regions to higher levels of Aβ aggregation, iron overload, and subsequent neurodegeneration, indicating changes preceding clinical symptoms. The vulnerability of distinct brain regions to amyloid beta (Aβ) and iron accumulation varies. Histological validation was performed on stained sections of ex-vivo human brains. Regional variations in susceptibility were linked to gene expression profiles. Iron and Aβ levels in ex-vivo brains were simultaneously quantified.

Current Advances and Material Innovations in the Search for Novel Treatments of Phenylketonuria.

Phenylketonuria (PKU) is a genetically inherited disease caused by a mutation of the gene encoding phenylalanine hydroxylase (PAH) and is the most common inborn error of amino acid metabolism. A deficiency of PAH leads to increased blood and brain levels of phenylalanine (Phe), which may cause permanent neurocognitive symptoms and developmental delays if untreated. Current management strategies for PKU consist of early detection through neonatal screening and implementation of a restrictive diet with minimal amounts of natural protein in combination with Phe-free supplements and low-protein foods to meet nutritional requirements. For milder forms of PKU, oral treatment with synthetic sapropterin (BH4), the cofactor of PAH, may improve metabolic control of Phe and allow for more natural protein to be included in the patient's diet. For more severe forms, daily injections of pegvaliase, a PEGylated variant of phenylalanine ammonia-lyase (PAL), may allow for normalization of blood Phe levels. However, the latter treatment has considerable drawbacks, notably a strong immunogenicity of the exogenous enzyme and the attached polymeric chains. Research for novel therapies of PKU makes use of innovative materials for drug delivery and state-of-the-art protein engineering techniques to develop treatments which are safer, more effective, and potentially permanent.

Simulation-based effective comparative analysis of neuron circuits for neuromorphic computation systems

The spiking neural networks (SNN) which are inspired by the human brain offers wider scope for application in the growth of neuromorphic computing systems due to their brain level computational capabilities, reduced power consumption, minimal data movement cost, and among other advantages. Spike-based neurons and synapses are the essential building blocks of SNN, and their efficient implementation is vital to its performance enhancement. In this regard, the design and implementation of spiking neurons have been the major focus among the researchers. In this paper, functioning of different leaky integrate fire (LIF)-based spiking neuron circuits like frequency adaptable CMOS-based LIF, resistor-capacitor-based (RC) LIF, and volatile memristor-based LIF are subjected to comparison. The work mainly focuses on revealing analysis of spike duration and amplitude, number of spikes produced during excitation period, threshold operation, field of application, and various other significant parameters of aforementioned neuron circuits. Extensive simulations of these circuits are carried out utilizing the Cadence Virtuoso simulation environment in order to validate their behavior. Further, a brief comparative analysis is executed considering into account the attributes like circuit complexity, supply voltage, firing rate, membrane capacitance, nature of input/output, refractory mechanism, and energy consumption per spike. This work seeks to assist researchers in selecting an appropriate LIF model to efficiently construct memristors and/or non-memristors based SNN for certain application.

Neuroprotective effects of punicalagin and/or micronized zeolite clinoptilolite on manganese-induced Parkinson's disease in a rat model: Involvement of multiple pathways.

Manganism, a central nervous system dysfunction correlated with neurological deficits such as Parkinsonism, is caused by the substantial collection of manganese chloride (MnCl2) in the brain. To explore the neuroprotective effects of natural compounds, namely, micronized zeolite clinoptilolite (ZC) and punicalagin (PUN), either individually or in combination, against MnCl2-induced Parkinson's disease (PD). Fifty male albino rats were divided into 5 groups (Gps). Gp I was used as the control group, and the remaining animals received MnCl2 (Gp II-Gp V). Rats in Gps III and IV were treated with ZC and PUN, respectively. Gp V received both ZC and PUN as previously reported for the solo-treated plants. ZC and/or PUN reversed the depletion of monoamines in the brain and decreased acetyl choline esterase activity, which primarily adjusted the animals' behavior and motor coordination. ZC and PUN restored the balance between glutamate/γ-amino butyric acid content and markedly improved the brain levels of brain-derived neurotrophic factor and nuclear factor erythroid 2-related factor 2/heme oxygenase-1 and decreased glycogen synthase kinase-3 beta activity. ZC and PUN also inhibited inflammatory and oxidative markers, including nuclear factor kappa-light-chain-enhancer of activated B cells, Toll-like receptor 4, nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 and caspase-1. Bcl-2-associated X-protein and B-cell leukemia/lymphoma 2 protein (Bcl-2) can significantly modify caspase-3 expression. ZC and/or PUN ameliorated PD in rats by decreasing the levels of endoplasmic reticulum (ER) stress markers (p-protein kinase-like ER kinase (PERK), glucose-regulated protein 78, and C/EBP homologous protein (CHOP)) and enhancing the levels of an autophagy marker (Beclin-1). ZC and/or PUN mitigated the progression of PD through their potential neurotrophic, neurogenic, anti-inflammatory, antioxidant, and anti-apoptotic activities and by controlling ER stress through modulation of the PERK/CHOP/Bcl-2 pathway.

GSP1-111 Modulates the Microglial M1/M2 Phenotype by Inhibition of Toll-like Receptor 2: A Potential Therapeutic Strategy for Depression.

Neuroinflammation plays a vital role in neurodegenerative diseases and neuropsychiatric disorders, and microglia and astrocytes chiefly modulate inflammatory responses in the central nervous system (CNS). Toll-like receptors (TLRs), which are expressed in neurons, astrocytes, and microglia in the CNS, are critical for innate immune responses; microglial TLRs can regulate the activity of these cells, inducing protective or harmful effects on the surrounding cells, including neurons. Therefore, regulating TLRs in microglia may be a potential therapeutic strategy for neurological disorders. We examined the protective effects of GSP1-111, a novel synthetic peptide for inhibiting TLR signaling, on neuroinflammation and depression-like behavior. GSP1-111 decreased TLR2 expression and remarkably reduced the mRNA expression of inflammatory M1-phenotype markers, including tumor necrosis factor (TNF)α, interleukin (IL)-1β, and IL-6, while elevating that of the M2 phenotype markers, Arg-1 and IL-10. In vivo, GSP1-111 administration significantly decreased the depression-like behavior induced by lipopolysaccharide (LPS) in a forced swim test and significantly reduced the brain levels of M1-specific inflammatory cytokines (TNFα, IL-1β, and IL-6). GSP1-111 prevented the LPS-induced microglial activation and TLR2 expression in the brain. Accordingly, GSP1-111 prevented inflammatory responses and induced microglial switching of the inflammatory M1 phenotype to the protective M2 phenotype. Thus, GSP1-111 could prevent depression-like behavior by inhibiting TLR2. Taken together, our results suggest that the TLR2 pathway is a promising therapeutic target for depression, and GSP1-111 could be a novel therapeutic candidate for various neurological disorders.

Intranasal Administration of Standardized Extract of Gotu Kola Leaves Against Nitroglycerine-Induced Recurrent Migraine-Like Pain in Rats

The present study aimed to determine the efficacy of intranasal administration of a standardized extract of Gotu kola, i.e., Centella asiatica (L.) Urban (INDCA-NS) with marker triterpenoids for the prevention of nitroglycerine- (NTG)-induced recurrent migraine in rats. Adult rats of both sexes in a group of 12 were administered intraperitoneal NTG (10 mg/kg) on alternate days (D1 to D9) and once daily intranasal solutions of either vehicle (saline, 50 µL/rat/day), sumatriptan (80 µL/rat/day of 12 mg/ml) as positive control, or INDCA-NS (10, 30, or 100 µg/rat/day) for 21 days. Behavioral and biochemical parameters related to concurrent migraine pain (facial expressions on the grimace scale, thermal hyperalgesia, mechanical allodynia, and plasma and brain levels of pituitary adenylate cyclase-activating polypeptide and nitric oxide), and stress (photophobia and cortisol levels in the brain and serum) were measured. The intranasal administration of INDCA-NS prevented NTG-induced migraine-like pain, photophobia, and stress in a dose-dependent manner. At the same time, sumatriptan alleviated pain and anxiety but not photophobia. In conclusion, the intranasal administration of INDCA-NS showed prophylactic efficacy against recurrent NTG-induced migraine pain in rats.

LDHB-deficient brain exhibits resistance to ischemic neuronal cell death due to increased vasodilation

Ischemic stroke triggers a cascade of metabolic and inflammatory events leading to neuronal death, particularly in the hippocampus. Here, we investigate the role of lactate metabolism in ischemic resistance using LDHB-deficient mice, which exhibit impaired lactate utilization. Contrary to expectations of severe neuronal damage due to metabolic defects, LDHB-deficient mice displayed significantly increased neuronal survival following ischemic insult. Magnetic resonance spectroscopy revealed elevated lactate levels in LDHB-deficient brains, which correlated with enhanced vasodilation of the posterior communicating artery (PComA) and increased extracellular PGE2 levels. These findings suggest that elevated lactate inhibits PGE2 reabsorption, promoting vasodilation and neuronal protection. Our results highlight lactate's potential role in neuroprotection and its therapeutic promise for ischemic stroke.