bioRxiv : the preprint server for biology
Dorman, LC;Nguyen, PT;Escoubas, CC;Vainchtein, ID;Xiao, Y;Lidsky, PV;Nakajo, H;Silva, NJ;Lagares-Linares, C;Wang, EY;Taloma, SE;Cuevas, B;Nakao-Inoue, H;Rivera, BM;Schwer, B;Condello, C;Andino, R;Nowakowski, TJ;Molofsky, AV;
PMID: 35233577 | DOI: 10.1101/2021.04.29.441889
Microglia, the innate immune cells of the brain, are exquisitely sensitive to dynamic changes in the neural environment. Using single cell RNA sequencing of the postnatal somatosensory cortex during topographic remapping, we identified a type I interferon (IFN-I) responsive microglia population that expanded with this developmental stressor. Using the marker gene IFITM3 we found that IFN-I responsive microglia were engulfing whole neurons. Loss of IFN-I signaling ( Ifnar1 -/- ) resulted in dysmorphic 'bubble' microglia with enlarged phagolysosomal compartments. We also observed a reduction in dead cells and an accumulation of neurons with double strand DNA breaks, a marker of cell stress. Conversely, IFN-I gain of function in zebrafish was sufficient to drive microglial engulfment of whole neurons. We identified IFITM3+ microglia in two murine disease models: SARS-CoV-2 infection and the 5xFAD model of Alzheimer's disease. These data reveal a novel role for IFN-I signaling in regulating efficient neuronal clearance by microglia.
Linker KE, Elabd MG, Tawadrous P, Cano M, Green KN, Wood MA, Leslie FM
PMID: 31949158 | DOI: 10.1038/s41467-019-14173-3
With the rise of e-cigarette use, teen nicotine exposure is becoming more widespread. Findings from clinical and preclinical studies show that the adolescent brain is particularly sensitive to nicotine. Animal studies have demonstrated that adolescent nicotine exposure increases reinforcement for cocaine and other drugs. However, the mechanisms that underlie these behaviors are poorly understood. Here, we report reactive microglia are critical regulators of nicotine-induced increases in adolescent cocaine self-administration. Nicotine has dichotomous, age-dependent effects on microglial morphology and immune transcript profiles. A multistep signaling mechanism involving D2 receptors and CX3CL1 mediates nicotine-induced increases in cocaine self-administration and microglial activation. Moreover, nicotine depletes presynaptic markers in a manner that is microglia-, D2- and CX3CL1-dependent. Taken together, we demonstrate that adolescent microglia are uniquely susceptible to perturbations by nicotine, necessary for nicotine-induced increases in cocaine-seeking, and that D2 receptors and CX3CL1 play a mechanistic role in these phenomena
Velez Torres, JM;Alkathery, T;Tjendra, Y;Zuo, Y;Kerr, DA;Gomez-Fernandez, C;
PMID: 36350307 | DOI: 10.1002/cncy.22659
High-risk human papillomavirus (HR-HPV) status is critical for the diagnosis, prognosis, and treatment of patients with oropharyngeal squamous cell carcinoma (OPSCC). Patients often present with enlarged cervical nodes, and fine-needle aspiration cytology (FNAC) is frequently the initial diagnostic procedure. Although p16 is the most widely used surrogate marker, problems with interpretation can limit its utility in FNAC. HR-HPV RNA in situ hybridization (ISH) has emerged as a specific way to assess HPV status on cell block preparations of cervical nodes. The authors evaluated the utility of HR-HPV ISH in conventional smears and liquid-based cytology (LBC) preparations of metastatic head and neck squamous cell carcinoma (SCC).Thirty-one aspirates of proven, HPV-related SCC (confirmed by p16 and/or HR-HPV ISH in corresponding surgical specimens) were selected. Ten aspirates of HPV-negative SCC were also retrieved. HR-HPV ISH was performed on 27 smears and 14 LBC preparations. All results were scored as positive, equivocal, or negative.Eighty-four percent of metastatic, HPV-related SCCs were positive for HR-HPV RNA ISH, with high number of signals (n = 19) and low number of signals (n = 7), whereas five HPV-related SCCs were equivocal. All metastatic, HPV-negative SCCs were negative for HR-HPV ISH.HR-HPV ISH can be reliably performed on smears or LBC preparations, particularly when cell blocks are unavailable or paucicellular. Results were easy to interpret when high numbers of signals were present but were challenging in aspirates with low or rare number of signals. The current study suggests that HR-HPV ISH could be used as the initial testing modality for determining HPV status in FNAC specimens of metastatic SCC.
Liu, X;Wang, Y;Zeng, Y;Wang, D;Wen, Y;Fan, L;He, Y;Zhang, J;Sun, W;Liu, Y;Tao, A;
PMID: 36876522 | DOI: 10.1111/all.15699
Spinal astrocytes contribute to chronic itch via sensitization of itch-specific neurons expressing gastrin-releasing peptide receptor (GRPR). However, whether microglia-neuron interactions contribute to itch remains unclear. In this study, we aimed to explore how microglia interact with GRPR+ neurons and promote chronic itch.RNA sequencing, quantitative real-time PCR, western blot, immunohistochemistry, RNAscope ISH, pharmacologic and genetic approaches were performed to examine the roles of spinal NLRP3 (The NOD-like receptor family, pyrin-containing domain 3) inflammasome activation and IL-1β-IL1R1 signaling in chronic itch. Grpr-eGFP and Grpr KO mice were used to investigate microglia-GRPR+ neuron interactions.We observed NLRP3 inflammasome activation and IL-1β production in spinal microglia under chronic itch conditions. Blockade of microglial activation and the NLRP3/caspase-1/IL-1β axis attenuated chronic itch and neuronal activation. Type 1 IL-1 receptor (IL-1R1) was expressed in GRPR+ neurons, which are essential for the development of chronic itch. Our studies also find that IL-1β+ microglia are localized in close proximity to GRPR+ neurons. Consistently, intrathecal injection of IL1R1 antagonist or exogenous IL-1β indicate that the IL-1β-IL-1R1 signaling pathway enhanced the activation of GRPR+ neurons. Furthermore, our results demonstrate that the microglial NLRP3/caspase-1/IL-1β axis contributes to several different chronic itches triggered by small molecules and protein allergens from the environment and drugs.Our findings reveal a previously unknown mechanism in which microglia enhances the activation of GRPR+ neurons through the NLRP3/caspase-1/IL-1β/IL1R1 axis. These results will provide new insights into the pathophysiology of pruritus and novel therapeutic strategies for patients with chronic itch.
Stempel AV, Stumpf A, Zhang HY, Özdoğan T, Pannasch U, Theis AK, Otte DM, Wojtalla A, Rácz I, Ponomarenko A, Xi ZX, Zimmer A, Schmitz D.
PMID: 27133464 | DOI: 10.1016/j.neuron.2016.03.034
Endocannabinoids (eCBs) exert major control over neuronal activity by activating cannabinoid receptors (CBRs). The functionality of the eCB system is primarily ascribed to the well-documented retrograde activation of presynaptic CB1Rs. We find that action potential-driven eCB release leads to a long-lasting membrane potential hyperpolarization in hippocampal principal cells that is independent of CB1Rs. The hyperpolarization, which is specific to CA3 and CA2 pyramidal cells (PCs), depends on the activation of neuronal CB2Rs, as shown by a combined pharmacogenetic and immunohistochemical approach. Upon activation, they modulate the activity of the sodium-bicarbonate co-transporter, leading to a hyperpolarization of the neuron. CB2R activation occurred in a purely self-regulatory manner, robustly altered the input/output function of CA3 PCs, and modulated gamma oscillations in vivo. To conclude, we describe a cell type-specific plasticity mechanism in the hippocampus that provides evidence for the neuronal expression of CB2Rs and emphasizes their importance in basic neuronal transmission.
Mishra D, Richard JE, Maric I, Porteiro B, Häring M, Kooijman S, Musovic S, Eerola K, López-Ferreras L, Peris E, Grycel K, Shevchouk OT, Micallef P, Olofsson CS, Wernstedt Asterholm I, Grill HJ, Nogueiras R, Skibicka KP.
PMID: 30865890 | DOI: 10.1016/j.celrep.2019.02.044
Chronic low-grade inflammation and increased serum levels of the cytokine IL-6 accompany obesity. For brain-produced IL-6, the mechanisms by which it controls energy balance and its role in obesity remain unclear. Here, we show that brain-produced IL-6 is decreased in obese mice and rats in a neuroanatomically and sex-specific manner. Reduced IL-6 mRNA localized to lateral parabrachial nucleus (lPBN) astrocytes, microglia, and neurons, including paraventricular hypothalamus-innervating lPBN neurons. IL-6 microinjection into lPBN reduced food intake and increased brown adipose tissue (BAT) thermogenesis in male lean and obese rats by increasing thyroid and sympathetic outflow to BAT. Parabrachial IL-6 interacted with leptin to reduce feeding. siRNA-mediated reduction of lPBN IL-6 leads to increased weight gain and adiposity, reduced BAT thermogenesis, and increased food intake. Ambient cold exposure partly normalizes the obesity-induced suppression of lPBN IL-6. These results indicate that lPBN-produced IL-6 regulates feeding and metabolism and pinpoints (patho)physiological contexts interacting with lPBN IL-6.
Geraghty AC, Gibson EM, Ghanem RA, Greene JJ, Ocampo A, Goldstein AK, Ni L, Yang T, Marton RM, Paşca SP, Greenberg ME, Longo FM, Monje M.
PMID: 31122677 | DOI: 10.1016/j.neuron.2019.04.032
Activity-dependent myelination is thought to contribute to adaptive neurological function. However, the mechanisms by which activity regulates myelination and the extent to which myelin plasticity contributes to non-motor cognitive functions remain incompletely understood. Using a mouse model of chemotherapy-related cognitive impairment (CRCI), we recently demonstrated that methotrexate (MTX) chemotherapy induces complex glial dysfunction for which microglial activation is central. Here, we demonstrate that remote MTX exposure blocks activity-regulated myelination. MTX decreases cortical Bdnf expression, which is restored by microglial depletion. Bdnf-TrkB signaling is a required component of activity-dependent myelination. Oligodendrocyte precursor cell (OPC)-specific TrkB deletion in chemotherapy-naive mice results in impaired cognitive behavioral performance. A small-molecule TrkB agonist rescues both myelination and cognitive impairment after MTX chemotherapy. This rescue after MTX depends on intact TrkB expression in OPCs. Taken together, these findings demonstrate a molecular mechanism required for adaptive myelination that is aberrant in CRCI due to microglial activation
Wallace ML, Huang KW, Hochbaum D, Hyun M, Radeljic G, Sabatini BL
PMID: 32043968 | DOI: 10.7554/eLife.51271
The lateral habenula (LHb) is an epithalamic brain structure critical for processing and adapting to negative action outcomes. However, despite the importance of LHb to behavior and the clear anatomical and molecular diversity of LHb neurons, the neuron types of the habenula remain unknown. Here, we use high-throughput single-cell transcriptional profiling, monosynaptic retrograde tracing, and multiplexed FISH to characterize the cells of the mouse habenula. We find five subtypes of neurons in the medial habenula (MHb) that are organized into anatomical subregions. In the LHb, we describe four neuronal subtypes and show that they differentially target dopaminergic and GABAergic cells in the ventral tegmental area (VTA). These data provide a valuable resource for future study of habenular function and dysfunction and demonstrate neuronal subtype specificity in the LHb-VTA circuit
Maza, N;Wang, D;Kowalski, C;Stoveken, HM;Dao, M;Sial, OK;Giles, AC;Grill, B;Martemyanov, KA;
PMID: 35982154 | DOI: 10.1038/s41593-022-01135-0
Repeated exposure to opioids causes tolerance, which limits their analgesic utility and contributes to overdose and abuse liability. However, the molecular mechanisms underpinning tolerance are not well understood. Here, we used a forward genetic screen in Caenorhabditis elegans for unbiased identification of genes regulating opioid tolerance which revealed a role for PTR-25/Ptchd1. We found that PTR-25/Ptchd1 controls μ-opioid receptor trafficking and that these effects were mediated by the ability of PTR-25/Ptchd1 to control membrane cholesterol content. Electrophysiological studies showed that loss of Ptchd1 in mice reduced opioid-induced desensitization of neurons in several brain regions and the peripheral nervous system. Mice and C. elegans lacking Ptchd1/PTR-25 display similarly augmented responses to opioids. Ptchd1 knockout mice fail to develop analgesic tolerance and have greatly diminished somatic withdrawal. Thus, we propose that Ptchd1 plays an evolutionarily conserved role in protecting the μ-opioid receptor against overstimulation.
International journal of gynecological pathology : official journal of the International Society of Gynecological Pathologists
Stolnicu, S;Hoang, L;Zhou, Q;Iasonos, A;Terinte, C;Pesci, A;Aviel-Ronen, S;Kiyokawa, T;Alvarado-Cabrero, I;Oliva, E;Park, KJ;Soslow, RA;
PMID: 36044310 | DOI: 10.1097/PGP.0000000000000921
Although both the 2014 and 2020 World Health Organization (WHO) criteria require unequivocal glandular and squamous differentiation for a diagnosis of cervical adenosquamous carcinoma (ASC), in practice, ASC diagnoses are often made in tumors that lack unequivocal squamous and/or glandular differentiation. Considering the ambiguous etiologic, morphologic, and clinical features and outcomes associated with ASCs, we sought to redefine these tumors. We reviewed slides from 59 initially diagnosed ASCs (including glassy cell carcinoma and related lesions) to confirm an ASC diagnosis only in the presence of unequivocal malignant glandular and squamous differentiation. Select cases underwent immunohistochemical profiling as well as human papillomavirus (HPV) testing by in situ hybridization. Of the 59 cases originally classified as ASCs, 34 retained their ASC diagnosis, 9 were reclassified as pure invasive stratified mucin-producing carcinomas, 10 as invasive stratified mucin-producing carcinomas with other components (such as HPV-associated mucinous, usual-type, or ASCs), and 4 as HPV-associated usual or mucinous adenocarcinomas with benign-appearing squamous metaplasia. Two glassy adenocarcinomas were reclassified as poorly differentiated HPV-associated carcinomas based on morphology and immunophenotype. There were no significant immunophenotypic differences between ASCs and pure invasive stratified mucin-producing carcinomas with regard to HPV and other markers including p16 expression. Although limited by a small sample size, survival outcomes seemed to be similar between all groups. ASCs should be diagnosed only in the presence of unequivocal malignant glandular and squamous differentiation. The 2 putative glassy cell carcinomas studied did not meet our criteria for ASC and categorizing them as such should be reconsidered.
Journal of ovarian research
Zhang, Y;Zhang, X;Wang, H;Shen, D;
PMID: 35115032 | DOI: 10.1186/s13048-022-00949-7
As the leading cancer of the female reproductive tract, it is not uncommon for human papilloma virus (HPV)-associated cervical squamous cell carcinoma (HPV-CSCC) to metastasize to pelvic organs and lymph nodes in advanced stages. However, herein, we present a rare case in which superficial invasive HPV-CSCC metastasized to the unilateral ovary as a large mass by spreading directly through the endometrium and fallopian tubes and lymph-vascular space invasion. The case is so unexpected that the misdiagnosis most likely could be proceeded as a primary ovarian cancer.A 58-year-old postmenopausal woman presented vaginal bleeding for more than 4 months, never received hormonal treatment and had no family history of malignant diseases. Routine ultrasound revealed a 12 × 10 × 10 cm right ovarian mass. Intraoperative frozen section was diagnosed as a borderline Brenner tumour with local highly suspected invasive carcinoma. Accordingly, omentectomy surgery then occurred. Unbelievably, by observation under a microscope, immunohistochemistrial staining, and HPV RNA scope, we found that the carcinoma originated from the uterine cervix. In the uterine cervix, stage IA1 superficial invasive squamous carcinoma was found, and the carcinoma directly spread to the endometrium and bilateral fallopian tube, was planted into the right ovary and eventually grew as a large mass. Moreover, lymph-vascular space invasion (LVSI) was also discovered. To date, the patient has been given 6 cycles of chemotherapy and has experienced no recurrence.The diagnosis of superficial invasive cervical squamous cell carcinoma metastasizing to the ovary is very challenging for pathological doctors, especially in intraoperative consultations.
Science Translational Medicine
Frere, J;Serafini, R;Pryce, K;Zazhytska, M;Oishi, K;Golynker, I;Panis, M;Zimering, J;Horiuchi, S;Hoagland, D;Møller, R;Ruiz, A;Kodra, A;Overdevest, J;Canoll, P;Borczuk, A;Chandar, V;Bram, Y;Schwartz, R;Lomvardas, S;Zachariou, V;tenOever, B;
| DOI: 10.1126/scitranslmed.abq3059
The host response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can result in prolonged pathologies collectively referred to as post-acute sequalae of COVID-19 (PASC) or long COVID. To better understand the mechanism underlying long COVID biology, we compared the short- and long-term systemic responses in the golden hamster following either SARS-CoV-2 or influenza A virus (IAV) infection. Results demonstrated that SARS-CoV-2 exceeded IAV in its capacity to cause permanent injury to the lung and kidney and uniquely impacted the olfactory bulb (OB) and epithelium (OE). Despite a lack of detectable infectious virus, the OB and OE demonstrated myeloid and T cell activation, proinflammatory cytokine production, and an interferon response that correlated with behavioral changes extending a month post viral clearance. These sustained transcriptional changes could also be corroborated from tissue isolated from individuals who recovered from COVID-19. These data highlight a molecular mechanism for persistent COVID-19 symptomology and provide a small animal model to explore future therapeutics.
