Selected Grantee Publications
Local Tissue Response to a C-X-C Motif Chemokine Ligand 12 Therapy for Fecal Incontinence in a Rabbit Model
Ruetten et al., American Journal of Physiology—Gastrointestinal and Liver Physiology. 2025.
https://pubmed.ncbi.nlm.nih.gov/39745592
Obstetric anal sphincter injury (OASI) occurs in 2–7% of vaginal childbirths. Surgical interventions for OASI are suboptimal, with 30% of women reporting continued reduction in quality of life due to long-term fecal incontinence. Researchers used a 4- to 5-month-old female New Zealand white rabbit model for OASI to determine whether local C-X-C motif chemokine ligand 12 (CXCL12) injection reduces postinjury pathologies. Treatment with CXCL12 significantly reduced fibrosis. Untreated rabbits demonstrated reduced distinction of anal sphincter skeletal muscle layering and significantly increased the amount of fibrosis. Treatment with CXCL12 did not affect recruitment of CD34+ cells, the number of PAX7+ satellite cells, or innervation and vascularization of skeletal muscle. This pilot study demonstrates the potential of a novel therapeutic for OASI. Supported by ORIP (T32OD010957).
Prostatic Escherichia coli Infection Drives CCR2-Dependent Recruitment of Fibrocytes and Collagen Production
Scharpf et al., Disease Models & Mechanisms. 2025.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11789281
In men, lower urinary tract dysfunction (LUTD) is commonly linked to prostatic collagen accumulation through inflammation-mediated mechanisms. Researchers used 8- to 10-week-old male reporter mice, exposed to either sterile phosphate buffered saline (PBS) or Escherichia coli, to identify that circulating Lyz2+S100a4+Gli1+ myeloid-derived cells are recruited to the prostate to drive inflammation and collagen synthesis. Researchers also used 8- to 10-week-old male Ccr2‑/ - null and Ccr2+/- control mice, exposed to either sterile PBS or E. coli, to determine if Ccr2 is necessary for the fibrotic response to prostatic uropathogen infection. Results demonstrated that CCR2+ cells mediate the collagen abundance and fibrotic response to prostate inflammation. This study elucidates the cell types underlying prostate fibrosis and can be utilized to develop targeted therapies. Supported by ORIP (T32OD010957), NCI, NIDDK, and NIEHS.
A Murine Model of Trypanosoma brucei-Induced Myocarditis and Cardiac Dysfunction
Crilly et al., Microbiology Spectrum. 2025.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11792545
Trypanosoma brucei is a protozoan parasite that causes human and animal African trypanosomiases, HAT and AAT, respectively. Cardiac symptoms are commonly reported in HAT patients, and intracardiac parasites with accompanying myocarditis have been observed in both natural hosts and animal models for T. brucei infection. A clinically relevant, reproducible murine model for T. brucei–associated cardiomyopathy is currently unavailable. The researchers developed a 7- to 10-week-old C57Bl/6J male and female mouse model for T. brucei infection that demonstrates myocarditis, elevated serum levels of NT-proBNP, and electrocardiographic abnormalities, recapitulating the clinical features of infection. The results demonstrate the importance of interstitial space in T. brucei colonization and provide a relevant, reproducible murine model to investigate the pathogenesis and potential therapeutics of T. brucei-mediated heart damage. Supported by ORIP (T32OD011089, S10OD026859), NCI, and NIA.
Peripherally Mediated Opioid Combination Therapy in Mouse and Pig
Peterson et al., The Journal of Pain. 2025.
https://pubmed.ncbi.nlm.nih.gov/39542192
This study evaluates novel opioid combinations for pain relief with reduced side effects. Researchers investigated loperamide (a μ-opioid agonist) with either oxymorphindole or N‑benzyl-oxymorphindole—both δ-opioid receptor partial agonists—in mice (male and female) and pigs (male). These combinations produced synergistic analgesia across species without causing adverse effects or respiratory depression. The therapies significantly reduced hypersensitivity in post-injury models, outperforming morphine alone. These findings suggest that peripherally acting opioid combinations can offer effective, safer alternatives for pain management, potentially lowering opioid misuse and side effects. This approach could improve clinical strategies for treating chronic and acute pain with limited central opioid exposure. Supported by ORIP (T32OD010993), NHLBI, and NIDA.
Failure of Colonization Following Gut Microbiota Transfer Exacerbates DSS-Induced Colitis
Gustafson et al., Gut Microbes. 2025.
https://pubmed.ncbi.nlm.nih.gov/39812347/
Microorganisms that inhabit the gastrointestinal tract, known as the gut microbiome (GM), play a vital role in health and disease. Dysbiosis, the reduced richness of symbiotic commensals in the GM, exacerbates inflammation and increases inflammatory bowel disease (IBD) severity. Researchers used a mouse model for IBD to determine the role of GM composition, richness, and transfer methods on IBD disease severity. A comparison of GM transfer methods demonstrated that co-housing was not as efficient as embryonic transfer and cross-fostering. The GM of the donor and recipient during co-housing determined transfer efficiency. Transfer of a low richness GM to a recipient with high GM richness, followed by dextran sodium sulfate administration to induce IBD, resulted in significant weight loss, greater lesion severity, increased inflammatory response, and higher mortality rates. This study provides evidence regarding the role of GM composition and colonization in IBD modulation. Supported by ORIP (T32OD011126, U42OD010918) and NIGMS.
Single-Cell Transcriptomics Predict Novel Potential Regulators of Acute Epithelial Restitution in the Ischemia-Injured Intestine
Rose et al., American Journal of Physiology-Gastrointestinal and Liver Physiology. 2025.
https://pubmed.ncbi.nlm.nih.gov/39853303
Following ischemia in the small intestine, early barrier restoration relies on epithelial restitution to reseal the physical barrier and prevent sepsis. Pigs share a similar gastrointestinal anatomy, physiology, and microbiota with humans. Researchers used neonatal and juvenile, 2- to 6-week-old male and female Yorkshire cross pigs to determine upstream regulators of restitution. Single-cell sequencing of ischemia-injured epithelial cells demonstrated two sub-phenotypes of absorptive enterocytes, with one subset presenting a restitution phenotype. Colony-stimulating factor-1 (CSF1) was the only predicted upstream regulator expressed in juvenile jejunum compared with neonatal jejunum. An in vitro scratch wound assay using IPEC-J2 cells showed that BLZ945, a colony-stimulating factor 1 receptor antagonist, inhibited restitution. Ex vivo ischemia-injured neonatal pig jejunum treated with exogenous CSF1 displayed increased barrier function. This study could inform future research focused on developing novel therapeutics for intestinal barrier injury in patients. Supported by ORIP (T32OD011130, K01OD028207), NCATS, NICHD, and NIDDK.
The Widely Used Ucp1-Cre Transgene Elicits Complex Developmental and Metabolic Phenotypes
Halurkar et al., Nature Communications. 2025.
https://pubmed.ncbi.nlm.nih.gov/39824816
Bacterial artificial chromosome technology is instrumental to mouse transgenics, including in studies of highly thermogenic brown adipose tissue and energy-storing white adipose tissue. Researchers discovered that male and female Ucp1-CreEvdr transgenic mice, which are commonly used to study fat tissue, may have unintended effects on metabolism and development. Findings revealed that these mice show changes in both brown and white fat function and disruptions in gene activity, suggesting broader physiological impacts than previously thought. This study emphasizes the need for careful validation of genetic tools in research to ensure accurate results, highlighting the potential concerns in using the Ucp1-CreEvdr model in metabolic and developmental studies. Supported by ORIP (R21OD034470, R21OD031907) NCATS, NIDCR, and NIDDK.
Matrikine Stimulation of Equine Synovial Fibroblasts and Chondrocytes Results in an In Vitro Osteoarthritis Phenotype
Gagliardi et al., Journal of Orthopaedic Research. 2025.
https://pubmed.ncbi.nlm.nih.gov/39486895
Advancements in therapy development for osteoarthritis (OA) currently are limited due to a lack of physiologically relevant in vitro models. This study aimed to understand the effect of matrikine stimulation, using human recombinant fibronectin fragment containing domains 7–10 (FN7–10), on equine synovial fibroblasts and chondrocytes. Inflammatory cytokines, chemokines, and matrix degradation genes in equine synovial fibroblasts and chondrocytes were significantly altered in response to FN7–10 stimulation; marked upregulation was observed in interleukin-6 (IL-6), IL-4, IL-10, matrix metalloproteinase 1 (MMP1), MMP3, MMP13, CCL2/MCP1, and CXCL6/GCP-2 gene expression. Only IL-6 protein production was significantly increased in media isolated from cells stimulated with FN7–10. These results support the potential use of equine synovial fibroblasts and chondrocytes—employing FN7–10—as representative in vitro models to study OA. Supported by ORIP (T32OD011130) and NIAMS.
Biocompatibility and Bone Regeneration by Shape Memory Polymer Scaffolds
Gasson et al., Journal of Biomedical Materials Research Part A. 2025.
https://pubmed.ncbi.nlm.nih.gov/39404147
This study evaluates the potential of shape memory polymer (SMP) scaffolds for bone tissue engineering, focusing on their biocompatibility and ability to support bone regeneration. Researchers first demonstrated biocompatibility of SMP scaffolds in 12-week-old male Wistar rats and confirmed cell adhesion, proliferation, and differentiation, while promoting bone regeneration in 6 month-old male New Zealand white rabbits with induced bone defects. These scaffolds combine mechanical strength with the capacity to enhance biological healing, making them a promising tool for orthopedic applications. These findings highlight the potential of SMPs as a versatile platform for tissue engineering applications, combining structural support with biocompatibility to enhance bone repair and healing outcomes. Supported by ORIP (T32OD011083).
A Switch from Glial to Neuronal Gene Expression Alterations in the Spinal Cord of SIV-Infected Macaques on Antiretroviral Therapy
Mulka et al., Journal of Neuroimmune Pharmacology. 2024.
https://pubmed.ncbi.nlm.nih.gov/38862787/
Up to one-third of patients with HIV experience HIV-associated peripheral neuropathy, affecting sensory pathways in the spinal cord. Spinal cord sampling is limited in people with HIV. Researchers examined gene expression alterations in the spinal cords of simian immunodeficiency virus (SIV)-infected male pigtail macaques with and without antiretroviral therapy (ART), using RNA sequencing at key time points throughout infection. Results indicate a shift from glial cell-associated pathways to neuronal pathways in SIV-infected animals receiving ART. These findings suggest that neurons, rather than glia, are predominantly involved in ART-related neurotoxicity and offer new insights into therapeutic strategies for maintaining synaptic homeostasis. Supported by ORIP (U42OD013117, T32OD011089) and NINDS.