Brain mRNA Levels Research Articles

Relationship of cognitive measures to mRNA levels in lymphocytes from patients with schizophrenia and controls

Patients with schizophrenia show substantial cognitive deficits and abnormalities in neurotransmitter-related levels of mRNA in brain or peripheral blood lymphocytes. However, the relationship of cognitive deficits as measured by the MATRICS battery and mRNA levels in brain or lymphocytes has not been sufficiently explored. We measured levels of methylation or neurotransmitter-related mRNAs in lymphocytes of 38 patients with chronic schizophrenia (CSZ) and 33 non-psychotic controls (controls) by qPCR using TaqMan probes. We assessed cognitive function in these patients and controls with the MATRICS battery. We used correlation analysis and scatter plots to assess the relationship of lymphocyte mRNA levels to MATRICS domain and composite scores. CSZ subjects had a consistently negative correlation between mRNA levels in lymphocytes and MATRICS cognitive variables of speed of processing, attention-vigilance, working memory, visual learning, and overall composite score. It is uncertain whether these negative correlations represent a causative relation between specific mRNA levels and cognitive deficits. Controls had either positive correlations or non-significant correlations between mRNA and most of the MATRICS variables. There were statistically significant differences in the correlations between mRNA and MATRICS variables between CSZ vs controls for several mRNAs (DNMT1, DNMT3A, BDNF, NR3C1, FPRF3, CNTNAP2). Our data show a different relationship between mRNA levels in peripheral blood lymphocytes and MATRICS cognitive variables in CSZ vs controls. The substantive significance of these differences needs further investigation.

Association of TMEM106B with Cortical APOE Gene Expression in Neurodegenerative Conditions.

The e4 allele of the apolipoprotein E gene is the strongest genetic risk factor for sporadic Alzheimer's disease. Nevertheless, how APOE is regulated is still elusive. In a trans-eQTL analysis, we found a genome-wide significant association between transmembrane protein 106B (TMEM106B) genetic variants and cortical APOE mRNA levels in human brains. The goal of this study is to determine whether TMEM106B is mis-regulated in Alzheimer's disease or in other neurodegenerative conditions. Available genomic, transcriptomic and proteomic data from human brains were downloaded from the Mayo Clinic Brain Bank and the Religious Orders Study and Memory and Aging Project. An in-house mouse model of the hippocampal deafferentation/reinnervation was achieved via a stereotaxic lesioning surgery to the entorhinal cortex, and mRNA levels were measured using RNAseq technology. In human temporal cortices, the mean TMEM106B expression was significantly higher in Alzheimer's disease compared to cognitively unimpaired individuals. In the mouse model, hippocampal Tmem106b reached maximum levels during the early phase of reinnervation. These results suggest an active response to tissue damage that is consistent with compensatory synaptic and terminal remodeling.

Chronic Nicotine Consumption and Withdrawal Regulate Melanocortin Receptor, CRF, and CRF Receptor mRNA Levels in the Rat Brain.

Alterations in the various neuropeptide systems in the mesocorticolimbic circuitry have been implicated in negative effects associated with drug withdrawal. The corticotropin-releasing factor (CRF) and α-melanocyte-stimulating hormone are two peptides that may be involved. This study investigated the regulatory effects of chronic nicotine exposure and withdrawal on the mRNA levels of melanocortin receptors (MC3R, MC4R), CRF, and CRF receptors (CRFR1 and CRFR2) expressed in the mesocorticolimbic system. Rats were given drinking water with nicotine or without nicotine (control group) for 12 weeks, after which they continued receiving nicotine (chronic exposure) or were withdrawn from nicotine for 24 or 48 h. The animals were decapitated following behavioral testing for withdrawal signs. Quantitative real-time PCR analysis demonstrated that nicotine exposure (with or without withdrawal) increased levels of CRF and CRFR1 mRNA in the amygdala, CRF mRNA in the medial prefrontal cortex, and CRFR1 mRNA in the septum. Nicotine withdrawal also enhanced MC3R and MC4R mRNA levels in different brain regions, while chronic nicotine exposure was associated with increased MC4R mRNA levels in the nucleus accumbens. These results suggest that chronic nicotine exposure and withdrawal regulate CRF and melanocortin signaling in the mesocorticolimbic system, possibly contributing to negative affective state and nicotine addiction.

Homocysteine Metabolites Inhibit Autophagy, Elevate Amyloid Beta, and Induce Neuropathy by Impairing Phf8/H4K20me1-dependent Epigenetic Regulation of mTOR in Cystathionine β-Synthase-Deficient Mice.

The loss of cystathionine β-synthase (CBS), an important homocysteine (Hcy)-metabolizing enzyme or the loss of PHF8, an important histone demethylase participating in epigenetic regulation, causes severe intellectual disability in humans. Similar neuropathies were also observed in Cbs-/- and Phf8-/- mice. How CBS or PHF8 depletion can cause neuropathy was unknown. To answer this question, we examined a possible interaction between PHF8 and CBS using Cbs-/- mouse and neuroblastoma cell models. We quantified gene expression by RT-qPCR and Western blotting, mTOR-bound H4K20me1 by chromatin immunoprecipitation (CHIP) assay, and amyloid β (Aβ) by confocal fluorescence microscopy using anti-Aβ antibody. We found significantly reduced expression of Phf8, increased H4K20me1, increased mTOR expression and phosphorylation, and increased App, both on protein and mRNA levels in brains of Cbs-/- mice vs. Cbs+/- sibling controls. Autophagy-related Becn1, Atg5, and Atg7 were downregulated while p62, Nfl, and Gfap were upregulated on protein and mRNA levels, suggesting reduced autophagy and increased neurodegeneration in Cbs-/- brains. In mouse neuroblastoma N2a or N2a-APPswe cells, treatments with Hcy-thiolactone, N-Hcy-protein or Hcy, or Cbs gene silencing by RNA interference significantly reduced Phf8 expression and increased total H4K20me1 as well as mTOR promoter-bound H4K20me1. This led to transcriptional mTOR upregulation, autophagy downregulation, and significantly increased APP and Aβ levels. The Phf8 gene silencing increased Aβ, but not APP, levels. Taken together, our findings identify Phf8 as a regulator of Aβ synthesis and suggest that neuropathy of Cbs deficiency is mediated by Hcy metabolites, which transcriptionally dysregulate the Phf8- > H4K20me1- > mTOR- > autophagy pathway thereby increasing Aβ accumulation. This article is protected by copyright. All rights reserved.

DHA alleviates high glucose-induced mitochondrial dysfunction in Oreochromis niloticus by inhibiting DRP1-mediated mitochondrial fission

Dynamin-related protein 1 (DRP1) is a key regulator in the maintenance of mammalian glucose homeostasis, but the relevant information remains poorly understood on aquatic animals. In the study, DRP1 is formally described for the first time in Oreochromis niloticus. DRP1 encodes a peptide of 673 amino acid residues that contained three conserved domains: a GTPase domain, a dynamin middle domain and a dynamin GTPase effector domain. DRP1 transcripts are widely distributed in all of the detected seven organs/tissues, and the highest mRNA levels in brain. High-carbohydrate (45 %) fed fish showed a significant upregulation of liver DRP1 expression than that of control (30 %) group. Glucose administration upregulated liver DRP1 expression, with peak values observed at 1 h; then its expression returned to the basal value at 12 h. In the in vitro study, DRP1 over-expression significantly decreased mitochondrial abundance in hepatocytes. DHA significantly increased mitochondrial abundance, transcriptions of mitochondrial transcription factor A (TFAM) and mitofusin 1 and 2 (MFN1 and MFN2) and complex II and III activities of high glucose-treated hepatocyte, whereas the opposite was true for DRP1, mitochondrial fission factor (MFF) and fission (FIS) expression. Together, these findings illustrated that O. niloticus DRP1 is highly conserved, and it participated in glucose control of fish. DHA could alleviate high glucose-induced mitochondrial dysfunction of fish by inhibiting DRP1-mediated mitochondrial fission.

Germinated brown rice extract reduces brain lipid peroxidation and Aβ levels via regulations of BACE1, RAGE, IDE and LRP1 expressions in high fat/cholesterol diet-fed rats

A strong association presents between excessive amyloid-β (Aβ) buildup and oxidative stress with Alzheimer’s disease (AD). In view of the multifaceted neuroprotective effects of some dietary elements, the beneficial effect of germinated brown rice was investigated using a high fat/cholesterol diet (HFCD)-induced sporadic rat model of AD. Seven groups, including normal control, HFCD, and HFCD treated with Donepezil, Simvastatin, Probucol, and germinated brown rice ethyl acetate extract (GBR-EA; 100 and 200 mg/kg bw) were included in the present study. Biochemical assays, brain lipid peroxidation, mRNA and protein levels involved in Aβ processing and metabolism pathways were analyzed. HFCD-fed rats exhibited increased brain lipid peroxidation and Aβ levels, as well as altered expressions of proteins involved in Aβ generation, degradation and clearance. GBR-EA treatment groups showed significant reduction in lipid peroxidation and Aβ levels when compared to HFCD group. The effects of GBR-EA on Aβ levels are likely through the modulation of BACE1 and Presenilins, as well as induction of Aβ clearance and degradation. The findings revealed the potential use of germinated brown rice to attenuate HFCD diet-induced neurodegenerative alterations, likely due to reduced brain inflammation, as well as modulation of Aβ processing and metabolism pathways.

Abstract 348: Elucidation of SUMOylation machinery in human cancer cells and naked mole-rat tissues

Abstract Background: SUMOylation is a post-translational modification where small ubiquitin-like modifier (SUMO) proteins are conjugated to lysine residues of target proteins. SUMO proteins exist in all eukaryotes and participate in a catalytic cycle, which includes maturation, activation, conjugation, ligation, and de-modification. SUMOylation is known to regulate numerous molecular regulatory mechanisms such as: chromatin remodeling, DNA repair, immune responses, cell cycle progression, apoptosis, and the intracellular signal transduction. SUMOylation dysregulation is known to promote several diseases, including cancer cell survival. The unique traits of phenotypic and molecular adaptations found in naked mole rats (NMR) suggest high stability and effective functioning of the molecular machinery that counteract damage accumulation in its genome. NMR lifespan can reach up to 32 years and acquires a very efficient mechanism of resistance to cancer. This study aims to investigate the regulation of SUMO machinery between human cancer cells breast (MCF-7), colorectal (DLD-1), and neuroblastoma (SH-SY5Y)) and NMR brain and intestinal tissues, in order to find novel targets for cancer treatment. Results: The pairwise alignment identified the similarity of both SUMO genes and proteins including SUMO1, SUMO2/3, and SUMO components of Sentrin-specific protease isoforms (SENP 1-7), activation (SAE1 and Uba2), conjugation (Ubc9), and ligation isoforms (PIAS1-4) between NMR and human. In addition, qRT-PCR data revealed low expression of SUMO components at the mRNA level in NMR brain and intestinal tissues compared to MCF-7, DLD-1, and SH-SY5Y cell lines. On the contrary, PIAS4 expression is significantly higher in the NMR tissues compared to cancer cell lines. Protein analysis via Western blotting performed on MCF-7, DLD-1, and SH-SY5Y cell lines revealed similar levels to mRNA compared to NMR tissue. Ongoing studies are focusing on several functional assays to investigate effects of hUBE2I, hSENP1, and Myc/hPIAS4 effects on cytotoxicity and signaling properties of the cancer cells using techniques such as Microculture Tetrazolium (MTT), migration, invasion, and colony formation. The effect on cytotoxicity is also analyzed in relevance to clinical used treatments such as Doxorubicin in MCF-7, 5-Fluorouracil for DLD-1 and Methotrexate in SH-SY5Y. Conclusion: Expression analysis of SUMOylation machinery revealed lower expression of mRNA levels for SUMO components was observed in NMR tissues compared to all human cancer cells. However, PIAS4 expression was significantly higher in the NMR tissues compared to cancer cell lines. This data revealed important differences in NMR SUMOylation machinery (such as UBE2I, SENP1 and PIAS4) which provides a future therapeutic avenue to treat cancer. Citation Format: Mohammed Abdullah Mohammed Salih, Ritchie Williamson, Sriharsha Kantamneni. Elucidation of SUMOylation machinery in human cancer cells and naked mole-rat tissues [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 348.

Food deprivation differentially modulates gene expression of LPXRFa and kisspeptin systems in the brain-pituitary axis of half-smooth tongue sole (Cynoglossus semilaevis).

LPXRFa, also known as gonadotropin-inhibitory hormone (GnIH), and kisspeptin (Kiss) are two major hypothalamic peptides that modulate the reproductive axis of vertebrates, including teleosts. However, little information is available regarding the actions of nutritional status on the regulation of these two neuroendocrine systems in fish. Herein, we assessed the effects of starvation and refeeding on the expression of lpxrfa, kiss2 and their receptors (lpxrfa-r and kiss2r respectively) at the brain-pituitary level of half-smooth tongue sole (Cynoglossus semilaevis). Food deprivation for 4 weeks induced a rise in brain lpxrfa as well as brain and pituitary lpxrfa-r mRNA levels, and refeeding restored brain lpxrfa and lpxrfa-r expression back to normal. However, pituitary lpxrfa-r mRNA levels still remained high after 1 week of refeeding. Neither lpxrfa nor kiss2 transcripts in the pituitary were altered by fasting, but their mRNA levels increased significantly after 1 week of refeeding, and declined back to the control levels after 2 weeks of refeeding. None of brain kiss2 and kiss2r along with pituitary kiss2r transcripts were modified by the nutritional status. In summary, our results revealed an interaction between energy status and the elements of LPXRFa and Kiss systems in the brain-pituitary axis of half-smooth tongue sole. Food deprivation and refeeding differentially regulated the two systems, which provided additional evidence for the involvement of the LPXRFa and Kiss systems in the regulation of reproduction by energy balance in non-mammalian species.

Different MAPT haplotypes influence expression of total MAPT in postmortem brain tissue

The MAPT gene, encoding the microtubule-associated protein tau on chromosome 17q21.31, is result of an inversion polymorphism, leading to two allelic variants (H1 and H2). Homozygosity for the more common haplotype H1 is associated with an increased risk for several tauopathies, but also for the synucleinopathy Parkinson’s disease (PD). In the present study, we aimed to clarify whether the MAPT haplotype influences expression of MAPT and SNCA, encoding the protein α-synuclein (α-syn), on mRNA and protein levels in postmortem brains of PD patients and controls. We also investigated mRNA expression of several other MAPT haplotype-encoded genes. Postmortem tissues from cortex of fusiform gyrus (ctx-fg) and of the cerebellar hemisphere (ctx-cbl) of neuropathologically confirmed PD patients (n = 95) and age- and sex-matched controls (n = 81) were MAPT haplotype genotyped to identify cases homozygous for either H1 or H2. Relative expression of genes was quantified using real-time qPCR; soluble and insoluble protein levels of tau and α-syn were determined by Western blotting. Homozygosity for H1 versus H2 was associated with increased total MAPT mRNA expression in ctx-fg regardless of disease state. Inversely, H2 homozygosity was associated with markedly increased expression of the corresponding antisense MAPT-AS1 in ctx-cbl. PD patients had higher levels of insoluble 0N3R and 1N4R tau isoforms regardless of the MAPT genotype. The increased presence of insoluble α-syn in PD patients in ctx-fg validated the selected postmortem brain tissue. Our findings in this small, but well controlled cohort of PD and controls support a putative biological relevance of tau in PD. However, we did not identify any link between the disease-predisposing H1/H1 associated overexpression of MAPT with PD status. Further studies are required to gain a deeper understanding of the potential regulatory role of MAPT-AS1 and its association to the disease-protective H2/H2 condition in the context of PD.

Lethal yellow mutation causes anxiety, obsessive-compulsive behavior and affects the brain melanocortin system in males and females of mice.

Background The brain melanocortin system regulates numerous physiological functions and kinds of behavior. The agouti protein inhibits melanocortin receptors in melanocytes. The lethal yellow (AY) mutation puts the Agouti gene under the control of the Raly gene promotor and causes the agouti protein expression in the brain. In the present article, we investigated the effects of the AY mutation on brain mRNA levels of Agouti, Raly, and melanocortin-related genes such as Agrp, Pomc, Mc3r, Mc4r, and their relationship to behavior. Methods The experiment was performed on 6-month-old males and females of AY/a and a/a (control) mice. Anxiety and obsessive-compulsive behavior were studied in elevated plus-maze and marble-burying tests. The mRNA levels were quantified by qPCR. Results AY mutation caused anxiety in males and obsessive-compulsive behavior in females. Positive correlation between Agouti and Raly genes mRNA levels were shown in the hypothalamus, hippocampus, and frontal cortex in AY/a mice. Reduced RNA concentrations of Mc3r and Mc4r genes were found respectively in the hypothalamus and frontal cortex in AY/a males. The Raly gene expression positively correlates with mRNA concentrations of the Mc3r gene in the hypothalamus and the Mc4r gene in the hypothalamus and frontal cortex. Conclusion Possible association of obsessive-compulsive behavior with reduced Raly, Mc3r, or Mc4r gene expression is suggested.

MiR-200b-3p antagomir inhibits neuronal apoptosis in oxygen-glucose deprivation (OGD) model through regulating β-TrCP

BackgroundHypoxia-ischemic brain damage (HIBD) is a primary cause of morbidity and disability in survivors of preterm infants. We previously discovered that miR-200b-3p plays an important role in HIBD via targeting Slit2. This study was designed to identify novel targets of miR-200b-3p and investigate the relationship between miR-200b-3p and its downstream effectors. Methods and resultsCultured primary rat hippocampal neurons were used in the model of oxygen-glucose deprivation (OGD) and RT-qPCR was utilized to detect the alterations of miR-200b-3p in these cells following the OGD. Our study found that the expression of miR-200b-3p was up-regulated in neurons post OGD. Bioinformatics analysis identified that β transducin repeat-containing protein (β-TrCP) is a target gene of miR-200b-3p, and our luciferase reporter gene assay confirmed that miR-200b-3p can interact with β-TrCP mRNA. Hypoxia-ischemic brain damage was induced in three-day-old SD rats and inhibition of miR-200b-3p by injection of antagomir into bilateral lateral ventricles enhanced β-TrCP expression at both the mRNA and protein levels in rats' brains. TUNEL staining and CCK-8 assays found that the survival of hippocampal neurons in the miR-200b-3p antagomir group was improved significantly (p＜0.05), whereas apoptosis of neurons in the miR-200b-3p antagomir group was significantly decreased (p＜0.05), as compared with the OGD group. However, silencing of β-TrCP by β-TrCP siRNA impaired the neuroprotective effect of miR-200b-3p antagomir. H&E staining showed that miR-200b-3p attenuated the pathological changes in the hippocampal region of rats with HIBD. ConclusionOur study has demonstrated that β-TrCP is a target gene of miR-200b-3p and that inhibition of miR-200b-3p by antagomir attenuates hypoxia-ischemic brain damage via β-TrCP.

Prenatal thermal stress affects acute-phase proteins, heat shock protein 70, and circulating corticosterone in developing broiler embryos and neonates

Higher or lower incubation temperature may impose some degree of stress on developing poultry embryos. This study was designed to delineate the effects of prenatal thermal stress on serum levels of acute-phase proteins (APPs), namely ceruloplasmin (CPN) and alpha-1-acid glycoprotein (AGP), the regulation of brain mRNA levels of heat shock protein (Hsp) 70, and serum levels of corticosterone (CORT) in embryos and neonatal chicks. Hatching eggs were subjected to three thermal treatments; (i) standard optimum temperature throughout (SS: 37.8 °C and 56 % RH), (ii) heat stress for 12 h daily (HS: 40.0 °C and 56 % RH), and (iii) cold stress for 12 h daily 18 (CS: 30.2 °C and 56 % RH). The heat and cold stress treatments were imposed from the 10th to the 18th day of incubation (ED). Results showed that thermal stress had a negligible effect on hatchability rate and body temperatures of neonatal chicks. The CS treatment was detrimental to embryonic growth. The HS treatment elevated AGP (ED 16, ED 18, and post-hatch day 1), CPN (on post-hatch day 1), and CORT (ED 14). On the contrary, the CS embryos had reduced AGP (ED14, ED16, ED18, and post-hatch day 1), CPN (ED 16), and CORT (ED 14, ED 16, ED 18). The brain mRNA levels of Hsp70 were upregulated throughout the experimental period in both the HS and CS embryos and chicks. Based on these modifications, AGP, together with Hsp70 mRNA expression, could be considered effective biomarkers useful to evaluate the magnitude and the time response of embryos and neonatal chicks to prenatal thermal stress. It is concluded that developing chicken embryos have the ability to evoke APPs, Hsp70 and CORT reactions which are important to cope with thermal stress.

Deficiency of kynurenine 3-monooxygenase exacerbates impairment of prepulse inhibition induced by phencyclidine

Phencyclidine (PCP) causes mental symptoms that closely resemble schizophrenia through the inhibition of the glutamatergic system. The kynurenine (KYN) pathway (KP) generates metabolites that modulate glutamatergic systems such as kynurenic acid (KA), quinolinic acid (QA), and xanthurenic acid (XA). Kynurenine 3-monooxygenase (KMO) metabolizes KYN to 3-hydroxykynurenine (3-HK), an upstream metabolite of QA and XA. Clinical studies have reported lower KMO mRNA and higher KA levels in the postmortem brains of patients with schizophrenia and exacerbation of symptoms in schizophrenia by PCP. However, the association between KMO deficiency and PCP remains elusive. Here, we demonstrated that a non-effective dose of PCP induced impairment of prepulse inhibition (PPI) in KMO KO mice. KA levels were increased in the prefrontal cortex (PFC) and hippocampus (HIP) of KMO KO mice, but 3-HK levels were decreased. In wild-type C57BL/6 N mice, the PPI impairment induced by PCP is exacerbated by KA, while attenuated by 3-HK, QA and XA. Taken together, KMO KO mice were vulnerable to the PPI impairment induced by PCP through an increase in KA and a decrease in 3-HK, suggesting that an increase in the ratio of KA to 3-HK (QA and XA) may play an important role in the pathophysiology of schizophrenia.

Transcriptional Regulatory Role of NELL2 in Preproenkephalin Gene Expression.

Preproenkephalin (PPE) is a precursor molecule for multiple endogenous opioid peptides Leu-enkephalin (ENK) and Met-ENK, which are involved in a wide variety of modulatory functions in the nervous system. Despite the functional importance of ENK in the brain, the effect of brain-derived factor(s) on PPE expression is unknown. We report the dual effect of neural epidermal growth factor (EGF)-like-like 2 (NELL2) on PPE gene expression. In cultured NIH3T3 cells, transfection of NELL2 expression vectors induced an inhibition of PPE transcription intracellularly, in parallel with downregulation of protein kinase C signaling pathways and extracellular signal-regulated kinase. Interestingly, these phenomena were reversed when synthetic NELL2 was administered extracellularly. The in vivo disruption of NELL2 synthesis resulted in an increase in PPE mRNA level in the rat brain, suggesting that the inhibitory action of intracellular NELL2 predominates the activation effect of extracellular NELL2 on PPE gene expression in the brain. Biochemical and molecular studies with mutant NELL2 structures further demonstrated the critical role of EGF-like repeat domains in NELL2 for regulation of PPE transcription. These are the first results to reveal the spatio-specific role of NELL2 in the homeostatic regulation of PPE gene expression.

Involvement of T-bet and GATA3 transcription factors in Mesenchymal stem cells and royal jelly combination treatment in brain stroke

IntroductionMesenchymal stem cells (MSC) therapy is a promising therapeutic strategy to overcome the brain stroke side effects. However, it may be associated with long-term complications, including induction of inflammation. This project was designed to examine the effects of MSC administration and its combination with royal jelly (RJ) on the differentiation of T helper subsets. Material and methodsIn this project, the mice were divided to the six groups, including control (healthy without stroke), stroke (mice model of middle cerebral artery occlusion (MCAO)), treated with mouse MSC (mMSC), royal jelly (RJ), combination of mMSC and RJ (mMSC + RJ) and MSC conditioned medium (SUP). Thereafter, sticky test, brain mRNA levels of T-bet (transcription factor for Th1 subset), GATA3 (transcription factor for Th2 subset), and ROR-γ (transcription factor for Th17 subset) and percentage of myeloperoxidase (MPO) activities were explored in the groups. ResultsAdministration of mMSC and mMSC + RJ improved the sticky test times and decreased the MPO activities. Using mMSCs and RJ was associated with increased expression of T-bet and GATA3 transcription factors. Transplantation of mMSCs in combination with RJ reduced expression of T-bet in the infarcted tissue. ConclusionUsing mMSC may be associated with Th1-related inflammation in the long term. RJ co-administration significantly reduced the risks, hence, to decrease the plausible side effects of MSCs, it can be proposed to use RJ in combination with MSC to reduce stroke complications.

The Regulatory Role of H19/miR-181a/ATG5 Signaling in Perinatal Nicotine Exposure-Induced Development of Neonatal Brain Hypoxic-Ischemic Sensitive Phenotype.

Nicotine exposure either from maternal cigarette smoking or e-cigarette vaping is one of the most common risk factors for neurodevelopmental disease in offspring. Previous studies revealed that perinatal nicotine exposure programs a sensitive phenotype to neonatal hypoxic-ischemic encephalopathy (HIE) in postnatal life, yet the underlying mechanisms remain undetermined. The goal of the present study was to determine the regulatory role of H19/miR-181a/ATG5 signaling in perinatal nicotine exposure-induced development of neonatal brain hypoxic-ischemic sensitive phenotype. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps. All experiments were conducted in offspring pups at postnatal day 9 (P9). Perinatal nicotine exposure significantly enhanced expression of miR-181a but attenuated autophagy-related protein 5 (ATG5) mRNA and protein levels in neonatal brains. Of interest, miR-181a mimicking administration in the absence of nicotine exposure also produced dose-dependent increased hypoxia/ischemia (H/I)-induced brain injury associated with a decreased ATG5 expression, closely resembling perinatal nicotine exposure-mediated effects. Locked nucleic acid (LNA)-miR-181a antisense reversed perinatal nicotine-mediated increase in H/I-induced brain injury and normalized aberrant ATG5 expression. In addition, nicotine exposure attenuated a long non-coding RNA (lncRNA) H19 expression level. Knockdown of H19 via siRNA increased the miR-181a level and enhanced H/I-induced neonatal brain injury. In conclusion, the present findings provide a novel mechanism that aberrant alteration of the H19/miR-181a/AGT5 axis plays a vital role in perinatal nicotine exposure-mediated ischemia-sensitive phenotype in offspring and suggests promising molecular targets for intervention and rescuing nicotine-induced adverse programming effects in offspring.

Integrating human brain proteomes with genome-wide association data implicates novel proteins in post-traumatic stress disorder.

Genome-wide association studies (GWAS) have identified several risk loci for post-traumatic stress disorder (PTSD); however, how they confer PTSD risk remains unclear. We aimed to identify genes that confer PTSD risk through their effects on brain protein abundance to provide new insights into PTSD pathogenesis. To that end, we integrated human brain proteomes with PTSD GWAS results to perform a proteome-wide association study (PWAS) of PTSD, followed by Mendelian randomization, using a discovery and confirmatory study design. Brain proteomes (N=525) were profiled from the dorsolateral prefrontal cortex using mass spectrometry. The Million Veteran Program (MVP) PTSD GWAS (n=186,689) was used for the discovery PWAS, and the Psychiatric Genomics Consortium PTSD GWAS (n=174,659) was used for the confirmatory PWAS. To understand whether genes identified at the protein-level were also evident at the transcript-level, we performed a transcriptome-wide association study (TWAS) using human brain transcriptomes (N=888) and the MVP PTSD GWAS results. We identified 11 genes that contribute to PTSD pathogenesis via their respective cis-regulated brain protein abundance. Seven of 11 genes (64%) replicated in the confirmatory PWAS and 4 of 11 also had their cis-regulated brain mRNA levels associated with PTSD. High confidence level was assigned to 9 of 11 genes after considering evidence from the confirmatory PWAS and TWAS. Most of the identified genes are expressed in other PTSD-relevant brain regions and several are preferentially expressed in excitatory neurons, astrocytes, and oligodendrocyte precursor cells. These genes are novel, promising targets for mechanistic and therapeutic studies to find new treatments for PTSD.

Absence of Apolipoprotein E is associated with exacerbation of prion pathology and promotes microglial neurodegenerative phenotype

Prion diseases or prionoses are a group of rapidly progressing and invariably fatal neurodegenerative diseases. The pathogenesis of prionoses is associated with self-replication and connectomal spread of PrPSc, a disease specific conformer of the prion protein. Microglia undergo activation early in the course of prion pathogenesis and exert opposing roles in PrPSc mediated neurodegeneration. While clearance of PrPSc and apoptotic neurons have disease-limiting effect, microglia-driven neuroinflammation bears deleterious consequences to neuronal networks. Apolipoprotein (apo) E is a lipid transporting protein with pleiotropic functions, which include controlling of the phagocytic and inflammatory characteristics of activated microglia in neurodegenerative diseases. Despite the significance of microglia in prion pathogenesis, the role of apoE in prionoses has not been established. We showed here that infection of wild type mice with 22L mouse adapted scrapie strain is associated with significant increase in the total brain apoE protein and mRNA levels and also with a conspicuous cell-type shift in the apoE expression. There is reduced expression of apoE in activated astrocytes and marked upregulation of apoE expression by activated microglia. We also showed apoE ablation exaggerates PrPSc mediated neurodegeneration. Apoe−/− mice have shorter disease incubation period, increased load of spongiform lesion, pronounced neuronal loss, and exaggerated astro and microgliosis. Astrocytes of Apoe−/− mice display salient upregulation of transcriptomic markers defining A1 neurotoxic astrocytes while microglia show upregulation of transcriptomic markers characteristic for microglial neurodegenerative phenotype. There is impaired clearance of PrPSc and dying neurons by microglia in Apoe−/− mice along with increased level of proinflammatory cytokines. Our work indicates that apoE absence renders clearance of PrPSc and dying neurons by microglia inefficient, while the excess of neuronal debris promotes microglial neurodegenerative phenotype aggravating the vicious cycle of neuronal death and neuroinflammation.

APOE4 expression is associated with impaired autophagy and mitophagy in astrocytes.

APOE4 expression is associated with impaired autophagy and mitophagy in astrocytes.

Effect of Lipopolysaccharide and TNFα on Neuronal Ascorbic Acid Uptake.

Vitamin C (ascorbic acid: AA) uptake in neurons occurs via the sodium-dependent vitamin C transporter-2 (SVCT2), which is highly expressed in the central nervous system (CNS). During chronic neuroinflammation or infection, CNS levels of lipopolysaccharide (LPS) and LPS-induced tumor necrosis factor-α (TNFα) are increased. Elevated levels of LPS and TNFα have been associated with neurodegenerative diseases together with reduced levels of AA. However, little is known about the impacts of LPS and TNFα on neuronal AA uptake. The objective of this study was to examine the effect of LPS and TNFα on SVCT2 expression and function using in vitro and in vivo approaches. Treatment of SH-SY5Y cells with either LPS or TNFα inhibited AA uptake. This reduced uptake was associated with a significant decrease in SVCT2 protein and mRNA levels. In vivo exposure to LPS or TNFα also decreased SVCT2 protein and mRNA levels in mouse brains. Both LPS and TNFα decreased SLC23A2 promoter activity. Further, the inhibitory effect of LPS on a minimal SLC23A2 promoter was attenuated when either the binding site for the transcription factor Sp1 was mutated or cells were treated with the NF-κB inhibitor, celastrol. We conclude that inflammatory signals suppress AA uptake by impairing SLC23A2 transcription through opposing regulation of Sp1 and NF-κB factors.