Microbiology Commons^™

Phosphorylation Of Ryr1 At Ser2902 Decreases Ca2+ Leak In Skeletal Muscle And Susceptibility To Malignant Hyperthermia And Heat Stroke, Rachel Sue Zhen Yee, Chang Seok Lee, Ting Chang, Sung Yun Jung, Omar Yousif, Courtney Cavazos, John Colyer, Filip Van Petegem, George G Rodney, Susan L Hamilton

Faculty, Staff and Students Publications

The ryanodine receptor 1 (RYR1) is the sarcoplasmic reticulum (SR) Ca2+ release channel required for both skeletal muscle contraction and Ca2+ leak. Mutations in RYR1 cause malignant hyperthermia susceptibility (MHS) and enhanced sensitivity to heat stroke (ESHS), which can result in death due to excessive skeletal muscle thermogenesis upon exposure to volatile anesthetics or heat. Here, we investigated the molecular and physiological functions of phosphorylation of RYR1 at Ser2902 by the kinase SPEG (striated muscle preferentially expressed protein). Muscle from SPEG-deficient mice expressing RYR1 with a Ser2902 →Asp2902 (S2902D) point mutation to mimic phosphorylation by SPEG showed decreased SR Ca2+ …

Strain-Specific Variability In Viral Kinetics, Cytokine Response, And Cellular Damage In Air-Liquid Cultures Of Human Nasal Organoids After Infection With Sars-Cov-2, Gina M Aloisio, Trevor J Mcbride, Letisha Aideyan, Emily M Schultz, Ashley M Murray, Anubama Rajan, Erin G Nicholson, David Henke, Laura Ferlic-Stark, Amal Kambal, Hannah L Johnson, Elina A Mosa, Fabio Stossi, Sarah E Blutt, Pedro A Piedra, Vasanthi Avadhanula

Faculty, Staff and Students Publications

SARS-CoV-2 variants have demonstrated distinct epidemiological patterns and clinical presentations throughout the COVID-19 pandemic. Understanding variant-specific differences at the respiratory epithelium is crucial for understanding their pathogenesis. Here, we utilized human nasal organoid air-liquid interface (HNO-ALI) cell cultures to compare the viral replication kinetics, innate immune response, and epithelial damage of six different strains of SARS-CoV-2 (B.1.2, WA, Alpha, Beta, Delta, and Omicron). All variants replicated efficiently in HNO-ALIs, but with distinct replication kinetic patterns. The Delta variant exhibited delayed replication kinetics, achieving a steady state at 6 days post-infection compared to 3 days for other variants. Cytokine analysis revealed …

Exploring The Transformative Effects Of Calorie Restriction On The Lacrimal Gland In Adult Mice, Olivier Mauduit, Prashant Kumar, Kaitlin K Scholand, Emre Aksan, Laura Schaefer, Anmar Abu-Romman, Vanessa Delcroix, Zhiyuan Yu, Aude I Sindikubwabo, Ron Korstanje, Helen P Makarenkova, Cintia S De Paiva

Faculty, Staff and Students Publications

Advanced age is one of the most recognizable risk factors for dry eye. Dry eye disease affects millions worldwide and can result from age-related lacrimal gland dysfunction, which correlates with a decline in lacrimal gland secretory cell function and chronic inflammation. This study investigated the potential of calorie restriction to maintain lacrimal gland and ocular surface health. Adult female C57BL/6 J mice were subjected to a 40% calorie restriction for 4 months, starting at 6-7 months and continuing until 10-11 months. These mice were compared to controls fed ad libitum. Bulk RNA sequencing of lacrimal glands, conjunctiva, and cornea subjected …

Author Correction: Clonal Dynamics And Somatic Evolution Of Haematopoiesis In Mouse, Chiraag D Kapadia, Nicholas Williams, Kevin J Dawson, Caroline Watson, Matthew J Yousefzadeh, Duy Le, Kudzai Nyamondo, Sreeya Kodavali, Alex Cagan, Sarah Waldvogel, Xiaoyan Zhang, Josephine De La Fuente, Daniel Leongamornlert, Emily Mitchell, Marcus A Florez, Krzysztof Sosnowski, Rogelio Aguilar, Alejandra Martell, Anna Guzman, David Harrison, Laura J Niedernhofer, Katherine Y King, Peter J Campbell, Jamie Blundell, Margaret A Goodell, Jyoti Nangalia

Faculty, Staff and Students Publications

No abstract provided.

Plasma Proteome Correlations With Liver Stiffness In Pediatric Cholestasis Implicate Epithelial To Mesenchymal Transition, Benjamin L Shneider, Rupa S Kanchi, Sandra L Grimm, Sridevi Devaraj, Juliet Emamaullee, Jeremy Schraw, Philip J Lupo, Jorge A Bezerra, Kathleen M Loomes, John C Magee, Ronald J Sokol, Kasper S Wang, Alyssa Kriegmeier, Evelyn Hsu, Jean P Molleston, Philip Rosenthal, Rohit Kohli, Saul J Karpen, Simon P Horslen, M Kyle Jensen, Arianna Barbetta, Cristian Coarfa

Faculty, Staff and Students Publications

Background: Pediatric cholestatic liver diseases can be characterized by rapidly progressive fibrosis. A multicenter cross-sectional analysis of vibration-controlled elastography in biliary atresia (BA), alpha-1 antitrypsin deficiency (A1AT), and Alagille syndrome (ALGS) was leveraged to interrogate the plasma proteome relative to liver stiffness measurements (LSM).

Methods: Slow off-rate modified aptamer scanning profiling of >7000 proteins in plasma from 187 children with BA (n=93), A1AT (n=31), ALGS (n=46), and healthy pediatric controls (n=17) was performed, and correlations with LSM were undertaken.

Results: There was an abundance of LSM correlated proteins (BA n=2720, A1AT n=694, ALGS n=5968). Interestingly, a distinct plasma proteome was …

Nrf2 Hyperactivation As A Driver Of Radiotherapy Resistance And Suppressed Antitumor Immunity In Head And Neck Squamous Cell Carcinoma, Rutulkumar Patel, Kalil Saab, Lixia Luo, Yan Ma, Rashid Abdullah Osman, Nerissa T Williams, Jeffrey Everitt, Maciej J Zelazowski, Patricia Castro, William K Decker, William H Hudson, Jeffrey N Myers, Vlad C Sandulache, Mitchell J Frederick, Yvonne M Mowery, David G Kirsch

Faculty, Staff and Students Publications

Purpose: Alterations in the KEAP1/NFE2L2 (NRF2)/CUL3 pathway occur in ∼20% of human head and neck squamous cell carcinomas (HNSCC) and are associated with resistance to standard-of-care therapy. However, this pathway's role in radiotherapy resistance in HNSCC has not been well studied.

Experimental design: We generated genetically engineered mouse models and developed primary murine cancer cell lines harboring mutations commonly observed in human HNSCC, including inducible activation of PIK3CA and deletion of Trp53, with or without Keap1 loss. Primary tumors were initiated via 4-hydroxytamoxifen injection ± the tobacco carcinogen benzo[a]pyrene (BAP) into the oral buccal mucosa. Tumors were analyzed by Western …

Examining The Relationship Between Dysphagia, Eating-Related Symptoms, And Diet Quality Among Oropharyngeal Cancer Patients During Critical Stages Of Cancer Survivorship: The U-Dine Study, Beatrice Manduchi, Vlad C Sandulache, Ji Yun Tark, Shreela Sharma, Ruosha Li, Emily Roller, Andrew Bevelhimer, Katherine A Hutcheson, Marcia C De Oliveira Otto

Faculty, Staff and Students Publications

Background: Diet quality is a modifiable factor impacting treatment outcomes in oropharyngeal cancer (OPC), yet the effect of dysphagia and self-reported eating-related symptoms remains unclear. This study examined their associations with diet quality in OPC patients.

Methods: A cross-sectional analysis was conducted with two parallel cohorts from MD Anderson Cancer Center and Michael E. DeBakey Veterans Affairs Medical Center as part of the Uncovering the Long-Term Impact of OPC and Dysphagia on Dietary Quality and Nutrition Among Cancer Survivors (U-DINE) Study. Participants at varying survivorship stages (prediagnosis, 3-6 and 18+ months posttreatment) were assessed for dysphagia (DIGEST scale) and six …

Observational Activation Of Anterior Cingulate Cortical Neurons Coordinates Hippocampal Replay In Social Learning, Xiang Mou, Daoyun Ji

Faculty, Staff and Students Publications

Social learning enables a subject to make decisions by observing the actions of another. How neural circuits acquire relevant information during observation to guide subsequent behavior is unknown. Utilizing an observational spatial working memory task, we show that neurons in the rat anterior cingulate cortex (ACC) associated with spatial trajectories during self-running in a maze are reactivated when observing another rat running the same maze. The observation-induced ACC activities are reduced in error trials and are correlated with activities of hippocampal place cells representing the same trajectories. The ACC activities during observation also predict subsequent hippocampal place cell activities during …

A Novel Self-Inhaled Nicotine Exposure System In Murine Models Reveals Age-Dependent Metabolic Effects Of Nicotine, Xu Xu, Hailan Liu, Meng Yu, Qingzhuo Liu, Yongxiang Li, Yue Deng, Yuxue Yang, Jingjing Cheng, Yutian Liu, Mengjie Wang, Xing Fang, Longlong Tu, Olivia Z Ginnard, Kristine M Mcdermott, Darah Threat, Fuhui Wang, Meixin Sun, Xinming Liu, Jiamin Qiu, Xi Wu, Jinjing Jian, Tong Zhou, Megan E Burt, Sanika V Jossy, Junying Han, Chunmei Wang, Yongjie Yang, Yong Xu, Yuhan Shi

Faculty, Staff and Students Publications

Background: Nicotine is known to influence metabolism and body weight, yet existing murine models of nicotine exposure often fail to replicate human smoking behaviors accurately. To address this gap, we designed a cost-effective, self-administered nicotine inhalation system that allows mice to voluntarily inhale nicotine vapor generated from e-liquid.

Results: Using this system, we investigated the metabolic effects of nicotine exposure in adult and adolescent mice. Adult mice exposed to nicotine vapor for 10 days exhibited significant weight loss, which was rapidly regained upon cessation, paralleling human smoking patterns. In contrast, adolescent mice did not lose weight during nicotine exposure but …

Artificial Intelligence In Head And Neck Cancer: Towards Precision Medicine, Jacob Hagen, Logan Hornung, William Barham, Supratik Mukhopadhyay, Adam Bess, Kevin Contrera, Devraj Basu, Vlad Sandulache, Guillaume Spielmann, Sagar Kansara

Faculty, Staff and Students Publications

Over the past 20 years, the capabilities of artificial intelligence (AI) have gained significant interest. While AI has been implemented to various degrees in several disciplines, its unique applications in head and neck cancer (HNC) remain underdeveloped. This narrative review examines the existing body of literature regarding the use of AI in HNC. Studies to date have demonstrated AI’s utility across multiple phases of the HNC treatment continuum. Despite its promise, integrating AI into clinical practice faces several challenges, including concerns about system integrity, generalizability, privacy, and bias. In this review, we address these challenges and offer insights into future …

Barriers And Timely Postoperative Radiation Therapy In Head And Neck Cancer, Megan T Nguyen, Emily Kistner-Griffin, Reid Demass, Bhisham S Chera, Chanita Hughes Halbert, Katherine R Sterba, Elizabeth G Hill, Brian Nussenbaum, Anthony J Alberg, Vlad C Sandulache, David J Hernandez, Ryan S Jackson, Sidharth V Puram, Russel Kahmke, Nosayaba Osazuwa-Peters, Gail Jackson, Sue S Yom, Evan M Graboyes

Faculty, Staff and Students Publications

Importance: Initiation of postoperative radiation therapy (PORT) within 6 weeks of surgery is associated with improved outcomes among patients with head and neck squamous cell carcinoma. However, the relationship of barriers to care with timely PORT is unknown.

Objective: To categorize barriers to timely PORT, evaluate the association of barriers to care with initiation of timely PORT, and describe the primary reason for delay among patients without timely PORT.

Design, setting, and participants: This prospective cohort study at a US academic medical center included adults with head and neck squamous cell carcinoma undergoing curative-intent surgery with an indication for PORT. …

Detection Of Heterogeneous Resistance Mechanisms To Tyrosine Kinase Inhibitors From Cell-Free Dna, Heather A Parsons, Conor Messer, Katheryn Santos, Jakob Weiss, David Merrell, Brian P Danysh, Melissa E Hughes, Gregory J Kirkner, Ashka Patel, Julian Hess, Kerry Sendrick, Chip Stewart, Elizabeth Grant, Kristy Schlueter-Kuck, Albert Grinshpun, Nikhil Wagle, Jamunarani Veeraraghavan, Jose Pablo Leone, Rachel A Freedman, Otto Metzger, Rachel Schiff, Eric P Winer, Sara M Tolaney, Mothaffar Rimawi, Ian E Krop, Gad Getz, Nancy U Lin

Faculty, Staff and Students Publications

Though there has been substantial progress in the development of anti-human epidermal growth factor receptor 2 (HER2) therapies to treat HER2-positive metastatic breast cancer (MBC) within the past two decades, most patients still experience disease progression and cancer-related death. HER2-directed tyrosine kinase inhibitors can be highly effective therapies for patients with HER2-positive MBC; however, an understanding of resistance mechanisms is needed to better inform treatment approaches. We performed whole-exome sequencing on 111 patients with 73 tumor biopsies and 120 cell-free DNA samples to assess mechanisms of resistance. In 11 of 26 patients with acquired resistance, we identified alterations in previously …

Results Of Tor001: An Open-Label Single Patient Study Using Targeted Bacteriophage Therapy For The Treatment Of A Chronic Urinary Tract Infection, Jonathan D Cook, Payton B Hooey, Keiko C Salazar, Justin R Clark, Umesh Jain, Carlos Fernando, Hanjeong Harvey, Alexander Cervantes, Stephanie Omagari, Udi Blankstein, Andrew M Kropinski, Alan R Davidson, Karen L Maxwell, Lori L Burrows, Austen L Terwilliger, Anthony W Maresso, Greg J German

Faculty, Staff and Students Publications

Chronic urinary tract infections are persistent bacterial infections with the potential to drive antibiotic resistance. Like other persistent bacterial infections, intracellular bacterial reservoirs and biofilm formation hinder the clearance of pathogens despite long courses of antibiotic therapy. New strategies for treatment of these persistent infections are needed. Here we describe the results of an open-label individual patient study using bacteriophage therapy to treat a chronic urinary tract infection in an immunocompetent 72-year-old woman without underlying urolithiasis or indwelling devices. We co-administered HP3.1, HP3, and ES19 bacteriophages with demonstrated in vitro activity via bladder instillation, orally, and as a topical formulation. …

Elephant Endotheliotropic Herpesvirus 2 Infection In 5 African Elephants (Loxodonta Africana) At Multiple North American Zoological Institutions, Taylor J Willis, Anne Burgdorf-Moisuk, Maren Connolly, Jan Raines, Cameron Ratliff, Zoltan S Gyimesi, Erica Lipanovich, Genevive A Dumonceaux, Kathryn L Perrin, Lauren L Howard, Matthew E Kinney, Kirk Suedmeyer, Erin Latimer, Tiffany L Kim, Jessica R Watts, Jie Tan, Paul Ling

Faculty, Staff and Students Publications

Objective: To acknowledge that elephant endotheliotropic herpesvirus (EEHV) is a well-recognized major threat to Asian elephants (Elephas maximus) and can cause acute and often fatal hemorrhagic disease (HD). Historically, EEHV-HD has been less frequently identified in African elephants (Loxodonta africana). This case series describes 5 recent cases of EEHV2 infection in African elephants within managed care at 5 North American institutions.

Animals: 5 African elephants (L africana).

Clinical presentation: The cases involved 4-, 7-, and 10-year-old males that died despite receiving aggressive medical therapy and 4- and 14-year-old females that survived. Clinical signs included lethargy, decreased appetite, lameness, changes in …

Cathartocytosis: Jettisoning Of Cellular Material During Reprogramming Of Differentiated Cells, Jeffrey W Brown, Xiaobo Lin, Gabriel Anthony Nicolazzi, Xuemei Liu, Thanh Nguyen, Megan D Radyk, Joseph Burclaff, Jason C Mills

Faculty, Staff and Students Publications

Injury causes differentiated cells to undergo massive reprogramming to become proliferative and repair tissue via paligenosis. Gastric chief cells use paligenosis to reprogram into progenitor-like spasmolytic-polypeptide-expressing metaplasia (SPEM) cells. Stage 1 of paligenosis is the downscaling of mature cell architecture via a process involving lysosomes. Here, we notice that sulfated glycoproteins are not only digested during paligenosis but also excreted into the gland. Various genetic and pharmacological approaches show that endoplasmic reticulum membranes and secretory granule cargo are also excreted and that the process proceeds in parallel with but is mechanistically independent of autophagy. Three-dimensional light and electron microscopy demonstrated …

Placental Polycyclic Aromatic Hydrocarbon (Pah) Levels Are Associated With Spontaneous Preterm Birth, Gwendolynn Hummel, Sohini Banerjee, Vasanta Putluri, Inaara Malick, Grace Johnson, Abu Hena Mostafa Kamal, Chandra Shekar R Ambati, Nagireddy Putluri, Lori Showalter, Cynthia D Shope, Joseph Hagan, Kjersti M Aagaard, Bhagavatula Moorthy, Melissa A Suter

Faculty, Staff and Students Publications

While the cause of preterm birth (PTB) (i.e., delivery before 37 weeks of gestation) is likely multifactorial, ambient exposure to environmental chemicals has been postulated to play a role in its etiology. Our prior studies of exposure to polycyclic aromatic hydrocarbons (PAHs) in pregnancy have shown an increased level of placental PAH-induced bulky DNA adducts with increasing levels of PAH exposures. In this investigation, we hypothesized that higher levels of placental PAHs would be associated with an increased risk of PTB. Using gas chromatography and mass spectrometry (GC-MS/MS), we measured levels of benzo(a)pyrene (BaP), benzo(b)fluoranthene (BbF) and dibenz(a,h)anthracene (DBA) from …

Proteogenomic Characterization Unveils Biomarkers Associated With Chemoresistance In Muscle-Invasive Bladder Cancer, Matthew V Holt, Yongchao Dou, Meggie N Young, Alexander B Saltzman, Meenakshi Anurag, Jonathan T Lei, Antrix Jain, Mei Leng, Beom-Jun Kim, Lacey E Dobrolecki, Stefanie F Faucher, Sara Savage, Chenwei Wang, Zhiao Shi, Hugo Villanueva, Karoline Kremers, Kyle D Drinnon, Patricia D Castro, Michael M Ittmann, Mehak Mehboob Khatani, Sung Han Kim, Matthew J Ellis, Bing Zhang, Anna Malovannaya, Seth P Lerner

Faculty, Staff and Students Publications

To explore potential chemoresistance mechanisms and identify therapeutic opportunities in muscle-invasive bladder cancer (MIBC), we conduct comprehensive proteogenomic characterization of 46 pre- and 14 post-treatment MIBC tumors incorporating genomics, transcriptomics, proteomics, and phosphoproteomics. Multi-omics clustering not only recapitulated established molecular subtypes but also revealed subtypes associated with chemotherapy sensitivity. Protein isoform level analysis identifies protein abundance of a short isoform of ATAD1 and RAF family proteins as biomarkers of chemosensitivity. Integration of proteomic and phosphoproteomic data reveals Wnt signaling via GSK3B-S9 phosphorylation and the JAK/STAT pathway as potential targets to overcome chemoresistance. Correlations between PD-L1 and TROP-2/NECTIN-4 indicate an additive …

Sox2 Regulates Foregut Squamous Epithelial Homeostasis And Is Lost During Barrett’S Esophagus Development, Ramon U Jin, Yuanwei Xu, T Mamie Lih, Yang-Zhe Huang, Toni M Nittolo, Blake E Sells, Olivia M Dres, Jean S Wang, Qing K Li, Hui Zhang, Jason C Mills

Faculty, Staff and Students Publications

Esophageal adenocarcinoma is increasingly prevalent and is thought to arise from Barrett's esophagus (BE), a metaplastic condition in which chronic acid and bile reflux transforms the esophageal squamous epithelium into a gastric-intestinal glandular mucosa. The molecular determinants driving this metaplasia are poorly understood. We developed a human BE organoid biobank that recapitulates BE's molecular heterogeneity. Bulk and single-cell transcriptomics, supported by patient tissue analysis, revealed that BE differentiation reflects a balance between SOX2 (foregut/esophageal) and CDX2 (hindgut/intestinal) transcription factors. Using squamous-specific inducible Sox2-KO (Krt5CreER/+ Sox2Δ/Δ ROSA26tdTomato/+) mice, we observed increased basal proliferation, reduced squamous differentiation, and expanded metaplastic glands at …

Co-Targeting Bcl-Xl With Mcl-1 Induces Lethal Mitochondrial Dysfunction In Diffuse Mesothelioma, Yuan Xu, Cristian G Medina, Deborah R Surman, Lacey E Dobrolecki, Monica Vilchis, Maheshwari Ramineni, Susan G Hilsenbeck, Yanming Li, Naren Li, Siqi Wu, Jaylon C Aggison, Xi Chen, Yi Zhu, Ying H Shen, R Taylor Ripley

Faculty, Staff and Students Publications

Diffuse mesothelioma (DM) is a rare but highly aggressive and treatment resistant neoplasm with low survival rates. Effective therapeutic strategies are limited, and resistance to treatment is a major obstacle. Myeloid Cell Leukemia (MCL)-1 and B-cell leukemia (BCL)-xL are anti-apoptotic B-cell lymphoma 2 (Bcl-2) family proteins that block cell-intrinsic apoptosis through interactions on the mitochondrial outer membrane which contribute to therapeutic resistance.

We investigated whether B-cell homology domain (BH)-3 profiles were consistent between intra-patient fresh tumor sample, patient-derived cells (PDC), and patient-derived xenografts (PDX) by BH3 profiling; we observed striking consistency which enabled cross model comparisons. Next, we co-targeted BCL-xl …

Increased Fungal Burden In The Gastrointestinal Tract Of Brain-Dead Organ Donors, Erika J Nachman, Colleen K Ardis, A Kyle B Ardis, Javier Nieto, Madeline M Bresson, Clare M Robertson, Maggie N Seale, Nora M Villafuerte, Zhe Lyu, Eva C Preisner, Heather A Danhof, Sara C Di Rienzi, Yolanda T Becker, Robert A Britton

Faculty, Staff and Students Publications

Approximately 3% of organ transplant recipients will be diagnosed with an invasive fungal infection (IFI), with 10%-47% being fatal. The source of IFI is typically not known, but Candida spp. cause the majority of IFI cases. We obtained intestines from two types of organ donors, brain-dead (BD) (n = 7) and donation after circulatory death (DCD) (n = 5), to sample microbes from the mucosal surface and the lumen. BD donors were parenterally fed and treated with corticosteroids in the days before procurement, whereas DCD donors were enterally fed and not given corticosteroids. We found fungi present in …

Three Things We Can Do Now To Reduce The Risk Of Avian Influenza Spillovers, Kenneth B Yeh, William P Bahnfleth, Elaine Bradford, Carol Cardona, Kristen K Coleman, Peter J Hudson, Bernadeta Dadonaite, Rebecca J Hutchins, Anthony Maresso, C Raina Macintyre, Matthew Scotch

Faculty, Staff and Students Publications

No abstract provided.

Long-Chain Fatty Acids Promote Candida Albicans Gut Colonization By Restructuring The Fungal Cell Surface, Musfirat Shubaita

Dissertations and Theses (Open Access)

Long-chain fatty acids promote Candida albicans gut colonization by restructuring the fungal cell surface

Musfirat Shubaita, BS

Advisory Professor: J. Christian Perez, Ph.D.

The yeast Candida albicans is a facultative anaerobe residing in the human digestive tract. Although fungal genetic determinants of mammalian host colonization have been identified, little is known about signals and molecules in the intestinal environment that influence C. albicans proliferation. Previously unpublished data from the Perez lab showed that oleic acid, one of the most abundant long-chain fatty acids in nature, promotes C. albicans colonization of the murine intestine. The goal of this research is to …

Microbial Metabolite Regulation Of Microglial Ahr Signaling In Alzheimer’S Disease, Ghalya E. Alrousan

Dissertations and Theses (Open Access)

Introduction: Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by amyloid-β plaque accumulation, neuroinflammation, and cognitive decline. Recent evidence suggests that systemic factors, particularly the gut microbiota and its metabolites, play a significant role in shaping brain immune responses, including microglial activation. However, the mechanisms linking gut dysbiosis to microglial dysfunction in AD are poorly understood. The aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor responsive to tryptophan metabolites, has recently gained attention as a key regulator of neuroinflammation and microglial function. I hypothesize that the loss of beneficial microbial AHR ligands, specifically indole derivatives, during aging and AD …

Nerve-To-Cancer Transfer Of Mitochondria During Cancer Metastasis, Gregory Hoover, Shila Gilbert, Olivia Curley, Clémence Obellianne, Mike T Lin, William Hixson, Terry W Pierce, Joel F Andrews, Mikhail F Alexeyev, Yi Ding, Ping Bu, Fariba Behbod, Daniel Medina, Jeffrey T Chang, Gustavo Ayala, Simon Grelet

Faculty, Staff and Students Publications

The nervous system has a pivotal role in cancer biology, and pathological investigations have linked intratumoural nerve density to metastasis1. However, the precise impact of cancer-associated neurons and the communication channels at the nerve–cancer interface remain poorly understood. Previous cancer denervation models in rodents and humans have highlighted robust cancer dependency on nerves, but the underlying mechanisms that drive nerve-mediated cancer aggressivity remain unknown2,3. Here we show that cancer-associated neurons enhance cancer metabolic plasticity by transferring mitochondria to cancer cells. Breast cancer denervation and nerve–cancer coculture models confirmed that neurons significantly improve tumour energetics. …

Low-Dose Metformin Requires Brain Rap1 For Its Antidiabetic Action, Hsiao-Yun Lin, Weisheng Lu, Yanlin He, Yukiko Fu, Kentaro Kaneko, Peimeng Huang, Ana B De La Puente-Gomez, Chunmei Wang, Yongjie Yang, Feng Li, Yong Xu, Makoto Fukuda

Faculty, Staff and Students Publications

Metformin is the most commonly prescribed antidiabetes drug, yet its precise mechanism of action remains controversial. Previous studies have suggested that metformin acts peripherally by reducing hepatic glucose output and altering gut functions. Here, we report a neural mechanism via the small guanosine triphosphatase Ras-related protein 1 (Rap1). Mice with forebrain-specific Rap1 knockout exhibited resistance to the antidiabetic effects of low-dose metformin while remaining sensitive to other antidiabetic agents. Centrally administered metformin inhibited brain Rap1 and reduced hyperglycemia. Conversely, forced activation of brain Rap1 increased glycemia and abolished the glycemic effect of metformin. Metformin activated a specific subset of neurons …

Single-Cell Transcriptomics Reveals Biomarker Heterogeneity Linked To Cdk4/6 Inhibitor Resistance In Breast Cancer Cell Lines, Ilenia Migliaccio, Martina Bonechi, Dario Romagnoli, Giulia Boccalini, Francesca Galardi, Cristina Guarducci, Agostina Nardone, Rachel Schiff, Laura Biganzoli, Luca Malorni, Matteo Benelli

Faculty, Staff and Students Publications

Cyclin dependent kinases 4 and 6 inhibitors have brought great improvements in the treatment of luminal breast cancer, but resistance is a major clinical hurdle. Multiple biomarkers of resistance have been proposed, but none is currently utilized in clinical practice. By performing single-cell RNA sequencing of seven palbociclib-naïve luminal breast cancer cell lines and palbociclib-resistant derivatives, we show that established biomarkers and pathways related to CDK4/6i resistance present marked intra- and inter- cell-line heterogeneity. Transcriptional features of resistance could be already observed in naïve cells correlating with levels of sensitivity (IC50) to palbociclib. Resistant derivatives showed transcriptional clusters that significantly …

Phosphoglycerate Mutase Regulates Treg Differentiation Through Control Of Serine Synthesis And One-Carbon Metabolism, Wesley H Godfrey, Judy J Lee, Shruthi Shanmukha, Kaho Cho, Xiaojing Deng, Chandra Shekar R Ambati, Vasanta Putluri, Abu Hena Mostafa Kamal, Paul M Kim, Nagireddy Putluri, Michael D Kornberg

Faculty, Staff and Students Publications

The differentiation and suppressive functions of regulatory CD4 T cells (Tregs) are supported by a broad array of metabolic changes, providing potential therapeutic targets for immune modulation. In this study, we focused on the regulatory role of glycolytic enzymes in Tregs and identified phosphoglycerate mutase (PGAM) as being differentially overexpressed in Tregs and associated with a highly suppressive phenotype. Pharmacologic or genetic inhibition of PGAM reduced Treg differentiation and suppressive function while reciprocally inducing markers of a pro-inflammatory, T helper 17 (Th17)-like state. The regulatory role of PGAM was dependent on the contribution of 3-phosphoglycerate (3 PG), the PGAM substrate, …

Dietary Lipids Induce Ppard And Bcl6 To Repress Macrophage Il-23 Induction After Intestinal Injury And Lps Exposure, Ashleigh M Gil, Daniel F Zegarra-Ruiz, Wan-Jung Wu, Kendra Norwood, Adrien Assie, Buck S Samuel, Angela M Major, Gretchen E Diehl, Andrea A Hill Mcalester

Faculty, Staff and Students Publications

Unresolved tissue damage is a common feature of Inflammatory Bowel Disease (IBD) that facilitates disease progression. Here, we showed that high animal fat diets (HFD), an environmental risk factor associated with IBD pathogenesis, suppress intestinal macrophage production of critical tissue repair responses after damage. This includes reduced IL-23 production, which drives downstream production of IL-22, which is needed for barrier repair. Indicating that dietary lipids interfere with responses to microbial molecules needed to induce barrier protective functions, we found oleic acid could directly suppress macrophage Il23a induction after lipopolysaccharide (LPS) treatment. Deleting the lipid transporter CD36 on macrophages restored the …

Mouse Metastable Epialleles Are Extremely Rare, Chathura J Gunasekara, Uditha Maduranga, Taylor Zhang, Jonathan N Wells, Maria S Baker, Eleonora Laritsky, Yumei Li, Cristian Coarfa, Yi Zhu, Robert A Waterland

Faculty, Staff and Students Publications

Metastable epialleles (MEs) are genomic loci at which epigenetic marks are established stochastically during early embryonic development and maintained during subsequent differentiation and throughout life, leading to stable epigenetic and phenotypic variation among genetically identical individuals. Although MEs were first described in mice over 20 years ago, the extent of epigenetic metastability in the mouse genome remains unknown. We present the first unbiased genome-wide screen for MEs in mice. Using deep whole-genome bisulfite sequencing across tissues derived from the three embryonic germ layers in isogenic C57BL/6J mice, we identified only 29 MEs, precisely localizing them and documenting their rarity. Consistent …

Altered Patterning Of Neural Activity In A Neuropathology, Clarissa Hoffman, Jingheng Cheng, Rodrigo Morales, Daoyun Ji, Yuri Dabaghian

Faculty, Staff and Students Publications

The dynamics of neural circuits and their role in mediating cellular and organismal phenomena remain poorly understood, despite numerous efforts to dissect these processes through precise instantaneous measurements or longer-time averages and approximations. We use an alternative approach: we investigate these dynamics at the system's mesoscale by analyzing spike trains and waveforms. These extended activity patterns carry robust, tractable information, are highly responsive to physiological specifics, and enable detailed tracking of circuit behavior. In particular, this methodology allows for characterizing the functionality of tau-pathology-afflicted hippocampal circuits and identifying circuit-level abnormalities that are missed by through traditional analyses. In healthy mice, …