Probes for INS

Interleukin 33 (IL33) signaling has been implicated in the establishment and maintenance of pregnancy and in pregnancy disorders. The goal of this project was to evaluate the role of IL33 signaling in rat pregnancy. The rat possesses hemochorial placentation with deep intrauterine trophoblast invasion; features also characteristic of human placentation. We generated and characterized a germline mutant rat model for IL33 using CRISPR/Cas9 genome editing. IL33 deficient rats exhibited deficits in lung responses to an inflammatory stimulus (Sephadex G-200) and to estrogen-induced uterine eosinophilia. Female rats deficient in IL33 were fertile and exhibited pregnancy outcomes (gestation length and litter size) similar to wild-type rats. Placental weight was adversely affected by the disruption of IL33 signaling. A difference in pregnancy-dependent adaptations to lipopolysaccharide (LPS) exposure was observed between wild-type and IL33 deficient pregnancies. Pregnancy in wild-type rats treated with LPS did not differ significantly from pregnancy in vehicle-treated wild-type rats. In contrast, LPS treatment decreased fetal survival rate, fetal and placental weights, and increased fetal growth restriction in IL33 deficient rats. In summary, a new rat model for investigating IL33 signaling has been established. IL33 signaling participates in the regulation of placental development and protection against LPS-induced fetal and placental growth restriction.

Circular RNAs (circRNAs) refer to a newly recognized family of non-coding RNA with single-stranded RNAs. Despite emerging evidence indicating that circRNAs are abundantly expressed in various tissues, especially in the brain and retina, the role of circRNAs in retinal function and diseases is still largely unknown. Circular Rims2 (circRims2) is highly expressed and conserved in both the human and mouse brains. However, little is known about the expression and function of circRims2 in the retina. In the current study, the high-throughput RNA-seq analysis reveals a high expression of circRims2 in the retina. In addition, it is found that circRims2 is mainly located in plexiform layers that contain synapses between retinal neurons. Knocking down circRims2 with short hairpin RNA through subretinal adeno-associated viral (AAV) delivery in the mice leads to the decrease of the thickness of the outer and inner segment (OS/IS) layers and outer nuclear layer (ONL), and cessation of scotopic and photopic electroretinogram responses. Furthermore, the current study finds that circRims2 deficiency evokes retinal inflammation and activates the tumor necrosis factor (TNF) signaling pathway. Therefore, circRims2 may play an important role in the maintenance of retinal structure and function, and circRims2 deficiency may lead to pathogenic changes in the retina.

The epigenetic abnormality is believed as a major driver for cancer initiation. Histone modification plays a vital role in tumor formation and progression. Particularly, alteration in histone acetylation has been highly associated with gene expression, cell cycle, as well as carcinogenesis. By analyzing glioblastoma (GBM)-related microarray from the GEO database and conducting chromatin immunoprecipitation-sequencing (ChIP-seq), we discovered that solute carrier family 30 member 3 (SLC30A3), a super enhancer (SE)-regulated factor, was significantly reduced in GBM tissues. Furthermore, histone deacetylase 1 (HDAC1), overexpressed in GBM tissues, could inhibit SLC30A3 expression by promoting histone H3K27ac deacetylation modification of the SE region of SLC30A3. Our functional validation revealed that SLC30A3 can inhibit the growth and metastatic spread of GBM cells in vitro and in vivo, and can activate the MAPK signaling pathway to promote apoptosis of GBM cells. Moreover, overexpression of HDAC1 resulted in a significant increase in DNA replication activity, a significant decline in apoptosis and cell cycle arrest in GBM cells. In a word, these findings indicate that combined epigenetic targeting of SLC30A3 by HDAC1 and SE is potentially therapeutically feasible in GBM.

Background: Most new HIV infections result from sexual interactions with infected but untreated individuals. Semen is the main vector for viral transmission globally, however, little is known regarding the anatomic origin and form of virus in semen. Methods: In this study, we were able to combine numerous new technologies to characterize the virus present in the semen during SIV infection. Six rhesus macaques (RM) were challenged intravenously with barcoded virus SIVmac239M. Semen and blood samples were collected longitudinally for 17 days post-infection with all male genital tract (MGT) and multiple lymphoid tissues collected at necropsy and subjected to quantitative PCR, next generation sequencing of the viral barcode, and tissue analysis (RNAscope, DNAscope and immunophenotyping). Semen was also collected from 6 animals chronically infected with SIVmac251 and in five CD4 depleted animals in acute phase and 2 weeks post ART initiation. Results: Extremely high levels of viral RNA (vRNA) were detected in seminal plasma (up to 10^9cp/ml) as well as comparable levels of cell associated vRNA and vDNA in seminal cells with detection starting as early as 4 days post-infection. RNAscope and immunophenotyping of seminal cells and MGT tissues revealed myeloid cells as the main source of virus (Fig. 1), while CD4+T cells were harboring vRNA in lymphoid tissues. Sequences show evidence of an early compartment between seminal and blood plasma and no difference in the env gene of virus present in semen/MGT and in Lymph Nodes. Finally, multinuclear giant cells harboring vRNA were the only source of virus in semen in chronically infected and in CD4 depleted RM. Moreover, vRNA + myeloid cells were highly present in semen after 2 weeks on ART.

Angiotensin (Ang) II signalling in the hypothalamic paraventricular nucleus (PVN) via angiotensin type-1a receptors (AT1R) regulates vasopressin release and sympathetic nerve activity - two effectors of blood pressure regulation. We determined the cellular expression and function of AT1R in the PVN of a rodent model of polycystic kidney disease (PKD), the Lewis Polycystic Kidney (LPK) rat, to evaluate its contribution to blood pressure regulation and augmented vasopressin release in PKD.PVN AT1R gene expression was quantified with fluorescent in-situ hybridisation in LPK and control rats. PVN AT1R function was assessed with pharmacology under urethane anaesthesia in LPK and control rats instrumented to record arterial pressure and sympathetic nerve activity.AT1R gene expression was upregulated in the PVN, particularly in CRH neurons, of LPK versus control rats. PVN microinjection of Ang II produced larger increases in systolic blood pressure in LPK versus control rats (36±5 vs. 17±2 mmHg; P<0.01). Unexpectedly, Ang II produced regionally heterogeneous sympathoinhibition (renal: -33%; splanchnic: -12%; lumbar no change) in LPK and no change in controls. PVN pre-treatment with losartan, a competitive AT1R antagonist, blocked the Ang II-mediated renal sympathoinhibition and attenuated the pressor response observed in LPK rats. The Ang II pressor effect was also blocked by systemic OPC-21268, a competitive V1A receptor antagonist, but unaffected by hexamethonium, a sympathetic ganglionic blocker.Collectively, our data suggest that upregulated AT1R expression in PVN sensitises neuroendocrine release of vasopressin in the LPK, identifying a central mechanism for the elevated vasopressin levels present in PKD.The Author(s).

Painful diabetic neuropathy (PDN) is an intractable and debilitating disease characterized by neuropathic pain and small-fiber degeneration. Given the prevalence of the disease, there is a dire need to identify new targets for the development of disease-modifying therapeutics for PDN. In patients with PDN, dorsal root ganglion (DRG) nociceptors become hyperexcitable and eventually degenerate, but the molecular mechanism underlying the phenomenon is unknown. We aim to identify the gene expression profile of the DRG neurons in PDN pathology to facilitate the discovery of novel druggable targets. Using a well-established mouse model of PDN, mice were either fed a regular diet (RD) or a high-fat diet (HFD) for 10 weeks. We used a single-cell RNA (scRNA-seq) sequencing approach to capture the changes in the DRG in an unbiased fashion. As expected, analysis of the scRNA-seq identified both neuronal and non-neuronal clusters and several differentially expressed genes. Interestingly, we saw two closely related non-peptidergic clusters expressing a Mas-related G protein-coupled receptor (Mrgprd). While there were no differences in the expression of Mrgprd in one of the clusters (NP1 Type1), there seemed to be a significant increase in the expression of Mrgprd in a cluster we refer to as the NP1 Type2. To determine the functional relevance of the overexpression of Mrgprd, we used in vivo 2-photon calcium imaging with Nav1.8 Cre-GCaMP6 animals fed an RD or HFD and examined whether administration of β-alanine (a known agonist of Mrgprd) in the hind paw would directly activate Mrgprd positive DRG neurons. We observed an increase in the number, as well as an increase in the magnitude of response in the HFD indicating the hyperexcitability of neurons expressing Mrgprd. Taken together, our data highlights an important role of the Mrgprd receptor in the generation and maintenance of hyperexcitability in a mouse model of PDN. NS104295-01.

Current treatments for chronic pain rely largely on opioids despite their substantial side effects and risk of addiction. Genetic studies have identified in humans key targets pivotal to nociceptive processing. In particular, a hereditary loss-of-function mutation in NaV1.7, a sodium channel protein associated with signaling in nociceptive sensory afferents, leads to insensitivity to pain without other neurodevelopmental alterations. However, the high sequence and structural similarity between NaV subtypes has frustrated efforts to develop selective inhibitors. Here, we investigated targeted epigenetic repression of NaV1.7 in primary afferents via epigenome engineering approaches based on clustered regularly interspaced short palindromic repeats (CRISPR)-dCas9 and zinc finger proteins at the spinal level as a potential treatment for chronic pain. Toward this end, we first optimized the efficiency of NaV1.7 repression in vitro in Neuro2A cells and then, by the lumbar intrathecal route, delivered both epigenome engineering platforms via adeno-associated viruses (AAVs) to assess their effects in three mouse models of pain: carrageenan-induced inflammatory pain, paclitaxel-induced neuropathic pain, and BzATP-induced pain. Our results show effective repression of NaV1.7 in lumbar dorsal root ganglia, reduced thermal hyperalgesia in the inflammatory state, decreased tactile allodynia in the neuropathic state, and no changes in normal motor function in mice. We anticipate that this long-lasting analgesia via targeted in vivo epigenetic repression of NaV1.7 methodology we dub pain LATER, might have therapeutic potential in management of persistent pain states.

Controlling primary afferent nociceptive input is a known route to analgesia. This path is exemplified by agonists of the mu opioid receptors that are expressed in nociceptive DRG neurons and can be activated by intrathecal or systemic opioid agonists. For other peripheral analgesic targets, the hypothesis is that similar neuronal expression would validate their development as analgesic agents. In this study, two potential candidates, the kappa opioid and adenosine A3 receptors, are evaluated in human DRG for transcript levels, across species expression, and cell type localization using RNA Scope multiplex fluorescence microscopy. The Kappa receptor shows strong species variation in expression. No expression is detectable in dog DRG, low expression in mouse and rat, and relatively high expression in human DRG. This prompted an anatomical localization study to determine which cell types in the human DRG express the Kappa receptor. In situ hybridization disclosed Kappa receptor expression in satellite glial cells (SGCs) and most neurons were surrounded by fluorescent signal. This result was verified using a second independent probe to a distinct region of the OPRK1 transcript. Essentially no signal was seen in DRG neurons. The adenosine A3 receptor (ADORA3) is another GPCR suggested as a peripheral analgesic drug target. ADORA3 shows strong species expression variation, being absent in mouse, and expressed at low levels in rat and dog DRG. In contrast, ADORA3 was abundant in human DRG, but restricted to SGCs. These data suggest peripherally targeted agonists for either receptor may not be effective analgesic agents. Intramural Research Program, Clinical Center, NIH.

Hypothalamic-pituitary-adrenal (HPA) axis dynamics are disrupted by opioids and may be involved in substance abuse; this persists during withdrawal and abstinence and is associated with co-morbid sleep disruption leading to vulnerability to relapse. We hypothesized that chronic sleep restriction (SR) alters the HPA axis diurnal rhythm and the sexually dimorphic response to acute stressor during opioid abstinence. We developed a rat model to evaluate the effect of persistent sleep loss during opioid abstinence on HPA axis dynamics in male and female rats. Plasma ACTH and corticosterone were measured diurnally and in response to acute restraint stress in rats Before (control) compared to During subsequent opioid abstinence without or with SR. Abstinence, regardless of sleep state, led to an increase in plasma ACTH and corticosterone in the morning in males. There was a tendency for higher PM plasma ACTH during abstinence in SR males (p = 0.076). ACTH and corticosterone responses to restraint were reduced in male SR rats whereas there was a failure to achieve the post-restraint nadir in female SR rats. There was no effect of the treatments or interventions on adrenal weight normalized to body weight. SR resulted in a dramatic increase in hypothalamic PVN AVP mRNA and plasma copeptin in male but not female rats. This corresponded to the attenuation of the HPA axis stress response in SR males during opioid abstinence. We have identified a potentially unique, sexually dimorphic role for magnocellular vasopressin in the control of the HPA axis during opioid abstinence and sleep restriction.

Growth hormone (GH) acts in several hypothalamic neuronal populations to modulate metabolism and the autoregulation of GH secretion via negative-feedback loops. However, few studies have investigated whether GH receptor (GHR) expression in specific neuronal populations is required for the homeostatic control of GH secretion and energy homeostasis. In the present study, we investigated the consequences of the specific GHR ablation in GABAergic (VGAT-expressing) or glutamatergic (VGLUT2-expressing) cells. GHR ablation in GABAergic neurons led to increased GH secretion, lean mass, and body growth in male and female mice. VGAT-specific GHR knockout (KO) male mice also showed increased serum insulin-like growth factor-1, hypothalamic Ghrh, and hepatic Igf1 messenger RNA levels. In contrast, normal GH secretion, but reduced lean body mass, was observed in mice carrying GHR ablation in glutamatergic neurons. GHR ablation in GABAergic cells increased weight loss and led to decreased blood glucose levels during food restriction, whereas VGLUT2-specific GHR KO mice showed blunted feeding response to 2-deoxy-D-glucose both in males and females, and increased relative food intake, oxygen consumption, and serum leptin levels in male mice. Of note, VGLUT2-cre female mice, independently of GHR ablation, exhibited a previously unreported phenotype of mild reduction in body weight without further metabolic alterations. The autoregulation of GH secretion via negative-feedback loops requires GHR expression in GABAergic cells. Furthermore, GHR ablation in GABAergic and glutamatergic neuronal populations leads to distinct metabolic alterations. These findings contribute to the understanding of the neuronal populations responsible for mediating the neuroendocrine and metabolic effects of GH.

Colorectal cancer (CRC) is the third leading cause of cancer in the United States, and inflammatory bowel disease patients have an increased risk of developing CRC due to chronic intestinal inflammation with it being the cause of death in 10% to 15% of inflammatory bowel disease patients. TIPE2 (TNF-alpha-induced protein 8-like 2) is a phospholipid transporter that is highly expressed in immune cells and is an important regulator of immune cell function.The azoxymethane/dextran sulfate sodium murine model of colitis-associated colon cancer (CAC) was employed in Tipe2 -/- and wild-type mice, along with colonoid studies, to determine the role of TIPE2 in CAC.Early on, loss of TIPE2 led to significantly less numbers of visible tumors, which was in line with its previously described role in myeloid-derived suppressor cells. However, as time went on, loss of TIPE2 promoted tumor progression, with larger tumors appearing in Tipe2 -/- mice. This was associated with increased interleukin-22/STAT3 phosphorylation signaling. Similar effects were also observed in primary colonoid cultures, together demonstrating that TIPE2 also directly regulated colonocytes in addition to immune cells.This work demonstrates that TIPE2 has dual effects in CAC. In the colonocytes, it works as a tumor suppressor. However, in the immune system, TIPE2 may promote tumorigenesis through suppressor cells or inhibit it through IL-22 secretion. Going forward, this work suggests that targeting TIPE2 for CRC therapy requires cell- and pathway-specific approaches and serves as a cautionary tale for immunotherapy approaches in general in terms of colon cancer, as intestinal inflammation can both promote and inhibit cancer.