Sheng, ZF;Zhang, H;Phaup, JG;Zheng, P;Kang, X;Liu, Z;Chang, HM;Yeh, ETH;Johnson, AK;Pan, HL;Li, DP;
PMID: 37041718 | DOI: 10.1093/cvr/cvad056
Chronic stress is a well-known risk factor for the development of hypertension. However, the underlying mechanisms remain unclear. Corticotropin-releasing hormone (CRH) neurons in the central nucleus of the amygdala (CeA) are involved in the autonomic responses to chronic stress. Here, we determined the role of CeA-CRH neurons in chronic stress-induced hypertension.Borderline hypertensive rats (BHRs) and Wistar-Kyoto (WKY) rats were subjected to chronic unpredictable stress (CUS). Firing activity and M-currents of CeA-CRH neurons were assessed, and a CRH-Cre-directed chemogenetic approach was used to suppress CeA-CRH neurons. CUS induced a sustained elevation of arterial blood pressure (ABP) and heart rate (HR) in BHRs, while in WKY rats, CUS-induced increases in ABP and HR quickly returned to baseline levels after CUS ended. CeA-CRH neurons displayed significantly higher firing activities in CUS-treated BHRs than unstressed BHRs. Selectively suppressing CeA-CRH neurons by chemogenetic approach attenuated CUS-induced hypertension and decreased elevated sympathetic outflow in CUS-treated BHRs. Also, CUS significantly decreased protein and mRNA levels of Kv7.2 and Kv7.3 channels in the CeA of BHRs. M-currents in CeA-CRH neurons were significantly decreased in CUS-treated BHRs compared with unstressed BHRs. Blocking Kv7 channel with its blocker XE-991 increased the excitability of CeA-CRH neurons in unstressed BHRs but not in CUS-treated BHRs. Microinjection of XE-991 into the CeA increased sympathetic outflow and ABP in unstressed BHRs but not in CUS-treated BHRs.CeA-CRH neurons are required for chronic stress-induced sustained hypertension. The hyperactivity of CeA-CRH neurons may be due to impaired Kv7 channel activity, which represents a new mechanism involved in chronic stress-induced hypertension.We found that hyperactivity of CRH neurons in the CeA, likely due to diminished Kv7 channel activity, play a major role in the development of chronic stress-induced hypertension. Our study suggests that CRH neurons in the brain may be targeted for treating chronic stress-induced hypertension. Thus, increasing Kv7 channel activity or overexpressing Kv7 channels in the CeA may reduce stress-induced hypertension. Further studies are needed to delineate how chronic stress diminishes Kv7 channel activity in the brain.
Lin, S;Zhu, MY;Tang, MY;Wang, M;Yu, XD;Zhu, Y;Xie, SZ;Yang, D;Chen, J;Li, XM;
PMID: 36260252 | DOI: 10.1007/s12264-022-00958-y
Defensive behaviors induced by innate fear or Pavlovian fear conditioning are crucial for animals to avoid threats and ensure survival. The zona incerta (ZI) has been demonstrated to play important roles in fear learning and fear memory, as well as modulating auditory-induced innate defensive behavior. However, whether the neuronal subtypes in the ZI and specific circuits can mediate the innate fear response is largely unknown. Here, we found that somatostatin (SST)-positive neurons in the rostral ZI of mice were activated by a visual innate fear stimulus. Optogenetic inhibition of SST-positive neurons in the rostral ZI resulted in reduced flight responses to an overhead looming stimulus. Optogenetic activation of SST-positive neurons in the rostral ZI induced fear-like defensive behavior including increased immobility and bradycardia. In addition, we demonstrated that manipulation of the GABAergic projections from SST-positive neurons in the rostral ZI to the downstream nucleus reuniens (Re) mediated fear-like defensive behavior. Retrograde trans-synaptic tracing also revealed looming stimulus-activated neurons in the superior colliculus (SC) that projected to the Re-projecting SST-positive neurons in the rostral ZI (SC-ZIrSST-Re pathway). Together, our study elucidates the function of SST-positive neurons in the rostral ZI and the SC-ZIrSST-Re tri-synaptic circuit in mediating the innate fear response.
British journal of pharmacology
DeBaker, MC;Mitten, EH;Rose, TR;de Velasco, EMF;Gao, R;Lee, AM;Wickman, K;
PMID: 36929333 | DOI: 10.1111/bph.16071
Drugs of abuse, including alcohol, increase dopamine (DA) in the mesocorticolimbic system via actions on DA neurons in the ventral tegmental area (VTA). Increased DA transmission can activate inhibitory G protein signaling pathways in VTA DA neurons, including those controlled by GABAB (GABAB R) and D2 DA (D2 R) receptors. Members of the R7 subfamily of Regulator of G protein Signaling (RGS) proteins can regulate inhibitory G protein signaling, but their influence in VTA DA neurons is unclear. Here, we investigated the influence of RGS6, an R7 RGS family member that has been implicated in the regulation of alcohol consumption in mice, on inhibitory G protein signaling VTA DA neurons.We used molecular, electrophysiological, and genetic approaches to probe the impact of RGS6 on inhibitory G protein signaling in VTA DA neurons, and on binge-like alcohol consumption, in mice.RGS6 is expressed in adult mouse VTA DA neurons and it modulates inhibitory G protein signaling in a receptor-dependent manner, tempering D2 R-induced somatodendritic currents and accelerating deactivation of synaptically evoked GABAB R-dependent responses. RGS6-/- mice exhibit diminished binge-like alcohol consumption, a phenotype recapitulated in female (but not male) mice lacking RGS6 selectively in VTA DA neurons.RGS6 negatively regulates GABAB R- and D2 R-dependent inhibitory G protein signaling pathways in mouse VTA DA neurons and exerts a sex-dependent positive influence on binge-like alcohol consumption in adult mice. As such, RGS6 may represent a new diagnostic and/or therapeutic target for alcohol use disorder.This article is protected by
Prendecki, M;Gulati, K;Pisacano, N;Pinheiro, D;Bhatt, T;Mawhin, M;Toulza, F;Masuda, E;Cowburn, A;Lodge, K;Tam, F;Roufosse, C;Pusey, C;McAdoo, S;
| DOI: 10.1002/art.42321
Objectives Spleen tyrosine kinase (SYK) is a cytoplasmic protein tyrosine kinase which plays a role in signalling via B cell and Fc receptors. Fc receptor engagement and signalling via SYK is thought to be important in anti-neutrophil cytoplasm antibody (ANCA) IgG-mediated neutrophil activation. In this study we investigate the role for SYK in ANCA induced myeloid cell activation and vasculitis pathogenesis. Methods Phosphorylation of SYK in myeloid cells from healthy controls and AAV patients was analysed using flow cytometry. The effect of SYK inhibition on MPO-ANCA IgG activation of cells was investigated using functional assays (IL-8 and ROS production) and targeted gene analysis using Nanostring. Total and phosphorylated SYK at sites of tissue inflammation in patients with AAV was assessed using immunohistochemistry and RNAscope in situ hybridisation. Results We identify increased phosphorylated SYK at critical activatory tyrosine residues in blood neutrophils and monocytes from patients with active AAV compared to remission patients or healthy controls. SYK is phosphorylated in vitro following MPO-ANCA IgG stimulation and SYK inhibition can prevent ANCA-mediated cellular responses. Using targeted gene expression analysis, we identify up-regulation of FcR and SYK-dependent signalling pathways following MPO-ANCA IgG stimulation. Finally, we show SYK is expressed and phosphorylated in tissue leucocytes at sites of organ inflammation in AAV. Conclusions These findings indicate that SYK plays a critical role in MPO-ANCA IgG-induced myeloid cell responses that SYK is activated in circulating and tissue immune cells in AAV, and SYK inhibition may therefore be a potential therapeutic option.
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
Rodriguez, LA;Kim, SH;Page, SC;Nguyen, CV;Pattie, EA;Hallock, HL;Valerino, J;Maynard, KR;Jaffe, AE;Martinowich, K;
PMID: 36369482 | DOI: 10.1038/s41386-022-01487-y
The lateral septum (LS) is a basal forebrain GABAergic region that is implicated in social novelty. However, the neural circuits and cell signaling pathways that converge on the LS to mediate social behaviors aren't well understood. Multiple lines of evidence suggest that signaling of brain-derived neurotrophic factor (BDNF) through its receptor TrkB plays important roles in social behavior. BDNF is not locally produced in LS, but we demonstrate that nearly all LS GABAergic neurons express TrkB. Local TrkB knock-down in LS neurons decreased social novelty recognition and reduced recruitment of neural activity in LS neurons in response to social novelty. Since BDNF is not synthesized in LS, we investigated which inputs to LS could serve as potential BDNF sources for controlling social novelty recognition. We demonstrate that selectively ablating inputs to LS from the basolateral amygdala (BLA), but not from ventral CA1 (vCA1), impairs social novelty recognition. Moreover, depleting BDNF selectively in BLA-LS projection neurons phenocopied the decrease in social novelty recognition caused by either local LS TrkB knockdown or ablation of BLA-LS inputs. These data support the hypothesis that BLA-LS projection neurons serve as a critical source of BDNF for activating TrkB signaling in LS neurons to control social novelty recognition.
Mamedova, E;Dmytriyeva, O;Rekling, JC;
PMID: 35704969 | DOI: 10.1016/j.npep.2022.102261
Thyrotropin-releasing hormone (TRH) plays a central role in metabolic homeostasis, and single-cell sequencing has recently demonstrated that vagal sensory neurons in the nodose ganglion express thyrotropin-releasing hormone receptor 1 (TRHR1). Here, in situ hybridization validated the presence of TRHR1 in nodose ganglion (NG) neurons and immunohistochemistry showed that the receptor is expressed at the protein level. However, it has yet to be demonstrated whether TRHR1 is functionally active in NG neurons. Using NG explants transduced with a genetically encoded Ca2+ indicator (GECI), we show that TRH increases Ca2+ in a subset of NG neurons. TRH-induced Ca2+ transients were briefer compared to those induced by CCK-8, 2-Me-5-HT and ATP. Blocking Na+ channels with TTX or Na+ substitution did not affect the TRH-induced Ca2+ increase, but blocking Gq signaling with YM-254890 abolished the TRH-induced response. Field potential recordings from the vagus nerve in vitro showed an increase in response to TRH, suggesting that TRH signaling produces action potentials in NG neurons. These observations indicate that TRH activates a small group of NG neurons, involving Gq pathways, and we hypothesize that these neurons may play a role in gut-brain signaling.
Karadagi A, Cavedon AG, Zemack H, Nowak G, Eybye ME, Zhu X, Guadagnin E, White RA, Rice LM, Frassetto AL, Strom S, Jorns C, Martini PGV, Ellis E
PMID: 32341402 | DOI: 10.1038/s41598-020-64017-0
Alpha 1-antitrypsin (AAT) deficiency arises from an inherited mutation in the SERPINA1 gene. The disease causes damage in the liver where the majority of the AAT protein is produced. Lack of functioning circulating AAT protein also causes uninhibited elastolytic activity in the lungs leading to AAT deficiency-related emphysema. The only therapy apart from liver transplantation is augmentation with human AAT protein pooled from sera, which is only reserved for patients with advanced lung disease caused by severe AAT deficiency. We tested modified mRNA encoding human AAT in primary human hepatocytes in culture, including hepatocytes from AAT deficient patients. Both expression and functional activity were investigated. Secreted AAT protein increased from 1,14 to 3,43?ᄉg/ml in media from primary human hepatocytes following mRNA treatment as investigated by ELISA and western blot. The translated protein showed activity and protease inhibitory function as measured by elastase activity assay. Also, mRNA formulation in lipid nanoparticles was assessed for systemic delivery in both wild type mice and the NSG-PiZ transgenic mouse model of AAT deficiency. Systemic intravenous delivery of modified mRNA led to hepatic uptake and translation into a functioning protein in mice. These data support the use of systemic mRNA therapy as a potential treatment for AAT deficiency
Takahashi, K;Kwok, JC;Sato, Y;Aguirre, GD;Miyadera, K;
PMID: 37220680 | DOI: 10.1016/j.visres.2023.108260
Congenital stationary night blindness (CSNB) is a group of inherited retinal diseases in which either rod-to-ON-bipolar cell (ON-BC) signaling, or rod function is affected leading to impaired vision under low light conditions. One type of CSNB is associated with defects in genes (NYX, GRM6, TRPM1, GPR179, and LRIT3) involved in the mGluR6 signaling cascade at the ON-BC dendritic tips. We have previously characterized a canine model of LRIT3-CSNB and demonstrated short-term safety and efficacy of an ON-BC targeting AAV-LRIT3 (AAVK9#4-shGRM6-cLRIT3-WPRE) gene therapy. Herein, we demonstrate long-term functional recovery and molecular restoration following subretinal injection of the ON-BC targeting AAV-LRIT3 vector in all eight treated eyes for up to 32 months. Following subretinal administration of the therapeutic vector, expression of the LRIT3 transgene, as well as restoration of mGluR6 signaling cascade member TRPM1, were confirmed in the outer plexiform layer (OPL) of the treated area. However, further investigation of the transgene LRIT3 transcript expression by RNA in situ hybridization (RNA-ISH) revealed off-target expression in non-BCs including the photoreceptors, inner nuclear, and ganglion cell layers, despite the use of a mutant AAVK9#4 capsid and an improved mGluR6 promoter designed to specifically transduce and promote expression in ON-BCs. While the long-term therapeutic potential of AAVK9#4-shGRM6-cLRIT3-WPRE is promising, we highlight the necessity for further optimization of AAV-LRIT3 therapy in the canine CSNB model prior to its clinical application.
Carbonaro, M;Wang, K;Huang, H;Frleta, D;Patel, A;Pennington, A;Desclaux, M;Moller-Tank, S;Grindley, J;Altarejos, J;Zhong, J;Polites, G;Poueymirou, W;Jaspers, S;Kyratsous, C;Zambrowicz, B;Murphy, A;Lin, JC;Macdonald, LE;Daly, C;Sleeman, M;Thurston, G;Li, Z;
PMID: 37058568 | DOI: 10.1126/sciadv.adf4490
Liver steatosis is an increasing health issue with few therapeutic options, partly because of a paucity of experimental models. In humanized liver rodent models, abnormal lipid accumulation in transplanted human hepatocytes occurs spontaneously. Here, we demonstrate that this abnormality is associated with compromised interleukin-6 (IL-6)-glycoprotein 130 (GP130) signaling in human hepatocytes because of incompatibility between host rodent IL-6 and human IL-6 receptor (IL-6R) on donor hepatocytes. Restoration of hepatic IL-6-GP130 signaling, through ectopic expression of rodent IL-6R, constitutive activation of GP130 in human hepatocytes, or humanization of an Il6 allele in recipient mice, substantially reduced hepatosteatosis. Notably, providing human Kupffer cells via hematopoietic stem cell engraftment in humanized liver mice also corrected the abnormality. Our observations suggest an important role of IL-6-GP130 pathway in regulating lipid accumulation in hepatocytes and not only provide a method to improve humanized liver models but also suggest therapeutic potential for manipulating GP130 signaling in human liver steatosis.
Hepatology (Baltimore, Md.)
Liu, T;Wang, Q;Zhou, L;Zhang, P;Mi, L;Qiu, X;Chen, Z;Kuang, H;Li, S;Lin, JD;
PMID: 35950514 | DOI: 10.1002/hep.32719
The mammalian liver harbors heterogeneous cell types that communicate via local paracrine signaling. Recent studies have delineated the transcriptomic landscape of the liver in NASH that provides insights into liver cell heterogeneity, intercellular crosstalk, and disease-associated reprogramming. However, the nature of intrahepatic signaling and its role in NASH progression remain obscure.Here, we performed transcriptomic analyses and identified cardiotrophin-like cytokine factor 1 (CLCF1), a member of the IL-6 family cytokines, as a cholangiocyte-derived paracrine factor that was elevated in the liver from diet-induced NASH mice and patients with NASH. Adenovirus-associated virus-mediated overexpression of CLCF1 in the liver ameliorated NASH pathologies in two diet-induced NASH models in mice, illustrating that CLCF1 induction may serve an adaptive and protective role during NASH pathogenesis. Unexpectedly, messenger RNA and protein levels of leukemia inhibitory factor receptor (LIFR), a subunit of the receptor complex for CLCF1, were markedly downregulated in NASH liver. Hepatocyte-specific inactivation of LIFR accelerated NASH progression in mice, supporting an important role of intrahepatic cytokine signaling in maintaining tissue homeostasis under metabolic stress conditions.Together, this study sheds light on the molecular nature of intrahepatic paracrine signaling during NASH pathogenesis and uncovers potential targets for therapeutic intervention.
Molecular cancer therapeutics
Martin, AL;Anadon, CM;Biswas, S;Mine, JA;Handley, KF;Payne, KK;Mandal, G;Chaurio, RA;Powers, JJ;Sprenger, KB;Rigolizzo, KE;Innamarato, P;Harro, CM;Mehta, S;Perez, BA;Wenham, RM;Conejo-Garcia, JR;
PMID: 35499393 | DOI: 10.1158/1535-7163.MCT-21-0872
Though chimeric antigen receptor (CAR) expressing T cells have proven success in hematologic malignancies, their effectiveness in solid tumors has been largely unsuccessful thus far. We found that some olfactory receptors are expressed in a variety of solid tumors of different histological subtypes, with a limited pattern of expression in normal tissues. Quantification of OR2H1 expression by RT-QPCR and western blot analysis of 17 normal tissues, 82 ovarian cancers of various histologies, 8 non-small cell lung cancers (NSCLC), and 17 breast cancers demonstrated widespread OR2H1 expression in solid epithelial tumors with expression in normal human tissues limited to the testis. CAR T cells recognizing the extracellular domain of the olfactory receptor OR2H1 were generated with a targeting motif identified through the screening of a phage display library and demonstrated OR2H1-specific cytotoxic killing in vitro and in vivo, using tumor cells with spontaneous expression of variable OR2H1 levels. Importantly, recombinant OR2H1 IgG generated with the VH/VL sequences of the CAR construct specifically detected OR2H1 protein signal in 60 human lung cancers, 40 ovarian carcinomas and 73 cholangiocarcinomas, at positivity rates comparable to mRNA expression and without OR2H1 staining in 58 normal tissues. CRISPR/Cas9-mediated ablation of OR2H1 confirmed targeting specificity of the CAR and the tumor-promoting role of OR2H1 in glucose metabolism. Therefore, T cells redirected against OR2H1-expressing tumor cells represent a promising therapy against a broad range of epithelial cancers, likely with an admissible toxicity profile.
Molecular therapy : the journal of the American Society of Gene Therapy
Du, W;Ergin, V;Loeb, C;Huang, M;Silver, S;Armstrong, AM;Huang, Z;Gurumurthy, CB;Staecker, H;Liu, X;Chen, ZY;
PMID: 37244253 | DOI: 10.1016/j.ymthe.2023.05.005
Patients with mutations in the TMPRSS3 gene suffer from recessive deafness DFNB8/DFNB10. For these patients, cochlear implantation is the only treatment option. Poor cochlear implantation outcomes are seen in some patients. To develop biological treatment for TMPRSS3 patients, we generated a knockin mouse model with a frequent human DFNB8 TMPRSS3 mutation. The Tmprss3A306T/A306T homozygous mice display delayed onset progressive hearing loss similar to human DFNB8 patients. Using AAV2 as a vector to carry a human TMPRSS3 gene, AAV2-hTMPRSS3 injection in the adult knockin mouse inner ear results in TMPRSS3 expression in the hair cells and the spiral ganglion neurons. A single AAV2-hTMPRSS3 injection in Tmprss3A306T/A306T mice of an average age of 18.5 months leads to sustained rescue of the auditory function to a level similar to wild-type mice. AAV2-hTMPRSS3 delivery rescues the hair cells and the spiral ganglions neurons. This study demonstrates successful gene therapy in an aged mouse model of human genetic deafness. It lays the foundation to develop AAV2-hTMPRSS3 gene therapy to treat DFNB8 patients, as a standalone therapy or in combination with cochlear implantation.