Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
Alvarez-Bagnarol, Y;García, R;Vendruscolo, LF;Morales, M;
PMID: 37270620 | DOI: 10.1038/s41386-023-01620-5
Opioid withdrawal signs, such as hyperalgesia, are manifestations of opioid use disorder that may contribute to opioid seeking and taking. We have previously identified an association between dorsal raphe (DR) neurons and the expression of hyperalgesia during spontaneous heroin withdrawal. Here, we found that chemogenetic inhibition of DR neurons decreased hyperalgesia during spontaneous heroin withdrawal in male and female C57/B6 mice. By neuroanatomy, we identified three major subtypes of DR neurons expressing μ-opioid receptors (MOR) that were activated in hyperalgesia during spontaneous withdrawal, those expressing vesicular GABA transporter (VGaT), glutamate transporter 3 (VGluT3), or co-expressing VGluT3 and tryptophan hydroxylase (TPH). In contrast, we identified a small population of DR-MOR neurons expressing solely TPH, which were not activated in hyperalgesia during spontaneous withdrawal. Collectively, these findings indicate a role of the DR in hyperalgesia during spontaneous heroin withdrawal mediated, in part, by the activation of local MOR-GABAergic, MOR-glutamatergic and MOR-co-releasing glutamatergic-serotonergic neurons. We found that specific chemogenetic inhibition of DR-VGaT neurons blocked hyperalgesia during spontaneous heroin withdrawal in male and female mice. Collectively, these findings indicate that DR-GABAergic neurons play a role in the expression of hyperalgesia during spontaneous heroin withdrawal.
Qian, X;DeGennaro, EM;Talukdar, M;Akula, SK;Lai, A;Shao, DD;Gonzalez, D;Marciano, JH;Smith, RS;Hylton, NK;Yang, E;Bazan, JF;Barrett, L;Yeh, RC;Hill, RS;Beck, SG;Otani, A;Angad, J;Mitani, T;Posey, JE;Pehlivan, D;Calame, D;Aydin, H;Yesilbas, O;Parks, KC;Argilli, E;England, E;Im, K;Taranath, A;Scott, HS;Barnett, CP;Arts, P;Sherr, EH;Lupski, JR;Walsh, CA;
PMID: 36228617 | DOI: 10.1016/j.devcel.2022.09.011
Kinesins are canonical molecular motors but can also function as modulators of intracellular signaling. KIF26A, an unconventional kinesin that lacks motor activity, inhibits growth-factor-receptor-bound protein 2 (GRB2)- and focal adhesion kinase (FAK)-dependent signal transduction, but its functions in the brain have not been characterized. We report a patient cohort with biallelic loss-of-function variants in KIF26A, exhibiting a spectrum of congenital brain malformations. In the developing brain, KIF26A is preferentially expressed during early- and mid-gestation in excitatory neurons. Combining mice and human iPSC-derived organoid models, we discovered that loss of KIF26A causes excitatory neuron-specific defects in radial migration, localization, dendritic and axonal growth, and apoptosis, offering a convincing explanation of the disease etiology in patients. Single-cell RNA sequencing in KIF26A knockout organoids revealed transcriptional changes in MAPK, MYC, and E2F pathways. Our findings illustrate the pathogenesis of KIF26A loss-of-function variants and identify the surprising versatility of this non-motor kinesin.
Arthritis Rheumatol. 2015 Apr 27.
Makki MS, Haseeb A, Haqqi TM.
PMID: 25917063 | DOI: 10.1002/art.39173
Abstract OBJECTIVE: Enhanced IL-6 expression plays an important role in the pathogenesis of osteoarthritis (OA). MCPIP1 is a novel post-transcriptional regulator of IL-6 expression and is targeted by miR-9. We investigated the MCPIP1 expression in OA cartilage and explored whether targeting of MCPIP1 by miR-9 contributes to enhanced IL-6 expression in OA. METHODS: Gene and protein expression in IL-1β-stimulated human OA chondrocytes/cartilage was determined by TaqMan assays and immunoblotting respectively. MCPIP1 and IL-6 mRNA expression at single cell level was analyzed using RNAScopeTM . MCPIP1 protein interaction with IL-6 mRNA was investigated using RNA immunoprecipitation (RIP). Transient transfections were used for siRNA mediated knockdown and overexpression of MCPIP1, its RNAse defective mutant, miR-9 or antagomir. Role of signaling pathways was evaluated using small molecule inhibitors. Binding of miR-9 with the "seed sequence" in the 3'UTR of MCPIP1 mRNA was investigated using a luciferase reporter assay. RESULTS: MCPIP1 mRNA expression was low but expression of miR-9 and IL-6 was high in the damaged OA cartilage. In IL-1β-stimulated OA chondrocytes expression of miR-9 and MCPIP1 was mutually exclusive and increase in miR-9 expression level correlated with reduced MCPIP1 expression and enhanced IL-6 expression. MCPIP1 protein directly binds with IL-6 mRNA and over-expression of wild type MCPIP1 destabilized the IL-6 mRNA. MCPIP1 expression was altered by overexpression or inhibition of miR-9. Transfection with miR-9 mimics inhibited the reporter activity and mutation of the "seed sequence" abolished the repression of reporter activity. CONCLUSIONS: These studies implicate miR-9-mediated suppression of MCPIP1 in OA pathogenesis via upregulation of IL-6 expression in IL-1β-stimulated human OA chondrocytes. This article is protected by copyright. All rights reserved.
Cancer Prev Res (Phila). 2015 May 19.
Dietary carcinogens, such as 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and chronic inflammation have each been implicated as etiological agents in prostate cancer. We hypothesized that bacterial prostatitis would accelerate PhIP-induced pre-invasive lesions in the rat prostate. Male Fischer 344 rats were assigned into 4 groups: Control (untreated), PhIP (200 ppm in the diet for 20 weeks), E. coli (prostatic inoculation in week 10), or PhIP+E. coli. Study animals were monitored for a total of 52 weeks and were euthanized as necessary based on strict criteria for health status and tumor burden. Animals treated with E. coli initially developed acute and chronic inflammation in all lobes of the prostate, whereas inflammation was observed predominantly in the ventral lobe at time of death. PhIP+E. coli-treated animals exhibited a marked decrease in survival compared to PhIP-alone treated animals as a result of an increase in the number of invasive cancers that developed at multiple sites including the skin, small intestine, and Zymbal's gland. Despite their earlier mortality, PhIP+E. coli-treated animals developed an increased average number of precancerous lesions within the prostate compared to PhIP-treated animals, with a significantly increased Ki-67 index. Multiplexed serum cytokine analysis indicated an increase in the level of circulating IL-6 and IL-12 in PhIP+E. coli-treated animals. Elevated serum IL-6 levels correlated with the development of precancerous lesions within the prostate. These results suggest that bacterial infections and dietary carcinogens - two conceivably preventable cancer risk factors - may synergistically promote tumorigenesis.
Short KR, Veeris R, Leijten LM, van den Brand JM, Jong VL, Stittelaar K, Osterhaus ADME, Andeweg A, van Riel D.
Short KR, Veeris R, Leijten LM, van den Brand JM, Jong VL, Stittelaar K, Osterhaus ADME, Andeweg A, van Riel D.
PMID: - | DOI: 10.1093/infdis/jix281
Severe influenza is often associated with disease manifestations outside the respiratory tract. Whilst pro-inflammatory cytokines can be detected in the lungs and blood of infected patients, the role of extra-respiratory organs in the production of pro-inflammatory cytokines is unknown. Here, we show that both pandemic H1N1 and highly pathogenic H5N1 virus induce expression of TNFα, IL-6 and IL-8 in the respiratory tract and central nervous system. In addition, H5N1 virus induced cytokines in the heart, pancreas, spleen, liver and jejunum. Together, these data suggest that extra-respiratory tissues contribute to systemic cytokine responses which may increase the severity of influenza.
Periyasamy P, Thangaraj A, Guo ML, Hu G, Callen S, Buch S.
PMID: 29760177 | DOI: 10.1523/JNEUROSCI.3474-17.2018
The present study demonstrates HIV-1 Tat-mediated epigenetic downregulation of microglial miR-124 and its association with microglial activation. Exposure of mouse primary microglia isolated from newborn pups of either sex to HIV-1 Tat resulted in decreased expression of primary miR-124-1, primary miR-124-2 as well as the mature miR-124. In parallel, HIV-1 Tat exposure to mouse primary microglial cellsresulted in increased expression of DNA methylation enzymes, such as DNMT1, DNMT3A, and DNMT3B that were also accompanied by increased global DNA methylation. Bisulfite-converted genomic DNA sequencing in the HIV-1 Tat exposed mouse primary microglial cellsfurther confirmed increased DNA methylation of the primary miR-124-1 and primary miR-124-2 promoters. Bioinformatic analyses identified MECP2 as a novel 3'-UTR target of miR-124. This was further validated in mouse primary microglial cells wherein HIV-1 Tat-mediated downregulation of miR-124 resulted in increased expression of MECP2, leading in turn to further repression of miR-124 via the feedback loop. In addition to MECP2, miR-124 also modulated the levels of STAT3 through its binding to the 3'-UTR, leading to microglial activation. Luciferase assays and Ago2 immunoprecipitation determined the direct binding between miR-124 and 3'-UTR of both MECP2 and STAT3. Gene silencing of MECP2 and DNMT1 and overexpression of miR-124 blocked HIV-1 Tat-mediated downregulation of miR-124 and microglial activation. In vitro findings were also confirmed in the basal ganglia of SIV-infected rhesus macaques (both sexes). In summary, our findings demonstrate a novel mechanism of HIV-1 Tat-mediated activation of microglia via downregulation of miR-124, leading ultimately to increased MECP2 and STAT3 signaling.
SIGNIFICANCE STATEMENT
Despite the effectiveness of combination antiretroviral therapy in controlling viremia, the CNS continues to harbor viral reservoirs. The persistence of low-level virus replication leads to the accumulation of early viral proteins including HIV-1 Tat protein. Understanding the epigenetic/molecular mechanism(s) by which viral proteins such as HIV-1 Tat can activate microglia is thus of paramount importance. This study demonstrated HIV-1 Tat-mediated DNA methylation of the miR-124 promoter leads to its downregulation with a concomitant upregulation of the MECP2-STAT3-IL6 resulting in microglial activation. These findings reveal an unexplored epigenetic/molecular mechanism(s) underlying HIV-1 Tat-mediated microglial activation, thereby providing a potential target for the development of therapeutics aimed at ameliorating microglial activation and neuroinflammation in the context of HIV-1 infection.
Zhu H, Meissner LE, Byrnes C, Tuymetova G, Tifft CJ, Proia RL
PMID: 32179479 | DOI: 10.1016/j.isci.2020.100957
The SUSD4 (Sushi domain-containing protein 4) gene encodes a complement inhibitor that is frequently deleted in 1q41q42 microdeletion syndrome, a multisystem congenital disorder that includes neurodevelopmental abnormalities. To understand SUSD4's role in the mammalian nervous system, we analyzed Susd4 knockout (KO) mice. Susd4 KO mice exhibited significant defects in motor performance and significantly higher levels of anxiety-like behaviors. Susd4 KO brain had abnormal "hairy" basket cells surrounding Purkinje neurons within the cerebellum and significantly reduced dendritic spine density in hippocampal pyramidal neurons. Neurons and oligodendrocyte lineage cells of wild-type mice were found to express Susd4 mRNA. Protein expression of the complement component C1q was increased in the brains of Susd4 KO mice. Our data indicate that SUSD4 plays an important role in neuronal functions, possibly via the complement pathway, and that SUSD4 deletion may contribute to the nervous system abnormalities in patients with 1q41q42 deletions
Chen, J;Gannot, N;Li, X;Zhu, R;Zhang, C;Li, P;
PMID: 36522525 | DOI: 10.1007/s12264-022-00994-8
The parabrachial nucleus (PBN) integrates interoceptive and exteroceptive information to control various behavioral and physiological processes including breathing, emotion, and sleep/wake regulation through the neural circuits that connect to the forebrain and the brainstem. However, the precise identity and function of distinct PBN subpopulations are still largely unknown. Here, we leveraged molecular characterization, retrograde tracing, optogenetics, chemogenetics, and electrocortical recording approaches to identify a small subpopulation of neurotensin-expressing neurons in the PBN that largely project to the emotional control regions in the forebrain, rather than the medulla. Their activation induces freezing and anxiety-like behaviors, which in turn result in tachypnea. In addition, optogenetic and chemogenetic manipulations of these neurons revealed their function in promoting wakefulness and maintaining sleep architecture. We propose that these neurons comprise a PBN subpopulation with specific gene expression, connectivity, and function, which play essential roles in behavioral and physiological regulation.
Becker, K;Weigelt, CM;Fuchs, H;Viollet, C;Rust, W;Wyatt, H;Huber, J;Lamla, T;Fernandez-Albert, F;Simon, E;Zippel, N;Bakker, RA;Klein, H;Redemann, NH;
PMID: 36371417 | DOI: 10.1038/s41598-022-23065-4
Retinopathies are multifactorial diseases with complex pathologies that eventually lead to vision loss. Animal models facilitate the understanding of the pathophysiology and identification of novel treatment options. However, each animal model reflects only specific disease aspects and understanding of the specific molecular changes in most disease models is limited. Here, we conducted transcriptome analysis of murine ocular tissue transduced with recombinant Adeno-associated viruses (AAVs) expressing either human VEGF-A, TNF-α, or IL-6. VEGF expression led to a distinct regulation of extracellular matrix (ECM)-associated genes. In contrast, both TNF-α and IL-6 led to more comparable gene expression changes in interleukin signaling, and the complement cascade, with TNF-α-induced changes being more pronounced. Furthermore, integration of single cell RNA-Sequencing data suggested an increase of endothelial cell-specific marker genes by VEGF, while TNF-α expression increased the expression T-cell markers. Both TNF-α and IL-6 expression led to an increase in macrophage markers. Finally, transcriptomic changes in AAV-VEGF treated mice largely overlapped with gene expression changes observed in the oxygen-induced retinopathy model, especially regarding ECM components and endothelial cell-specific gene expression. Altogether, our study represents a valuable investigation of gene expression changes induced by VEGF, TNF-α, and IL-6 and will aid researchers in selecting appropriate animal models for retinopathies based on their agreement with the human pathophysiology.
Nuclear isoform of FGF13 regulates post-natal neurogenesis in the hippocampus through an epigenomic mechanism
Yang, QQ;Zhai, YQ;Wang, HF;Cai, YC;Ma, XY;Yin, YQ;Li, YD;Zhou, GM;Zhang, X;Hu, G;Zhou, JW;
PMID: 34010636 | DOI: 10.1016/j.celrep.2021.109127
The hippocampus is one of two niches in the mammalian brain with persistent neurogenesis into adulthood. The neurogenic capacity of hippocampal neural stem cells (NSCs) declines with age, but the molecular mechanisms of this process remain unknown. In this study, we find that fibroblast growth factor 13 (FGF13) is essential for the post-natal neurogenesis in mouse hippocampus, and FGF13 deficiency impairs learning and memory. In particular, we find that FGF13A, the nuclear isoform of FGF13, is involved in the maintenance of NSCs and the suppression of neuronal differentiation during post-natal hippocampal development. Furthermore, we find that FGF13A interacts with ARID1B, a unit of Brahma-associated factor chromatin remodeling complex, and suppresses the expression of neuron differentiation-associated genes through chromatin modification. Our results suggest that FGF13A is an important regulator for maintaining the self-renewal and neurogenic capacity of NSCs in post-natal hippocampus, revealing an epigenomic regulatory function of FGFs in neurogenesis.
Sodium leak channel contributes to neuronal sensitization in neuropathic pain
Zhang, D;Zhao, W;Liu, J;Ou, M;Liang, P;Li, J;Chen, Y;Liao, D;Bai, S;Shen, J;Chen, X;Huang, H;Zhou, C;
PMID: 33766679 | DOI: 10.1016/j.pneurobio.2021.102041
Neuropathic pain affects up to 10% of the total population and no specific target is ideal for therapeutic need. The sodium leak channel (NALCN), a non-selective cation channel, mediates the background Na+ leak conductance and controls neuronal excitability and rhythmic behaviors. Here, we show that increases of NALCN expression and function in dorsal root ganglion (DRG) and dorsal spinal cord contribute to chronic constriction injury (CCI)-induced neuropathic pain in rodents. NALCN current and neuronal excitability in acutely isolated DRG neurons and spinal cord slices of rats were increased after CCI which were decreased to normal levels by NALCN-siRNA. Accordingly, pain-related symptoms were significantly alleviated by NALCN-siRNA-mediated NALCN knockdown and completely prevented by NALCN-shRNA-mediated NALCN knockdown in rats or by conditional NALCN knockout in mice. Our results indicate that increases in NALCN expression and function contribute to CCI-induced neuronal sensitization; therefore, NALCN may be a novel molecular target for control of neuropathic pain.
NK-B cell cross talk induces CXCR5 expression on natural killer cells
Rascle, P;Jacquelin, B;Petitdemange, C;Contreras, V;Planchais, C;Lazzerini, M;Dereuddre-Bosquet, N;Le Grand, R;Mouquet, H;Huot, N;Müller-Trutwin, M;
| DOI: 10.1016/j.isci.2021.103109
B cell follicles (BCFs) in lymph nodes (LNs) are generally exempt of CD8+ T and NK cells. African green monkeys (AGMs), a natural host of simian immunodeficiency virus (SIV), display NK cell-mediated viral control in BCF. NK cell migration into BCF in chronically SIVagm-infected AGM is associated with CXCR5+ NK cells. We aimed to identify the mechanism leading to CXCR5 expression on NK cells. We show that CXCR5+ NK cells in LN were induced following SIVagm infection. CXCR5+ NK cells accumulated preferentially in BCF with proliferating B cells. Autologous NK-B cell co-cultures in transwell chambers induced CXCR5+ NK cells. Transcriptome analysis of CXCR5+ NK cells revealed expression of bcl6 and IL6R. IL-6 induced CXCR5 on AGM and human NK cells. IL6 mRNA was detected in LN at higher levels during SIVagm than SIVmac infection and often produced by plasma cells. Our study reveals a mechanism of B cell-dependent NK cell regulation.
