Selected Grantee Publications
Extracted Plasma Cell-Free DNA Concentrations Are Elevated in Colic Patients With Systemic Inflammation
Bayless et al., Veterinary Sciences. 2024.
https://pmc.ncbi.nlm.nih.gov/articles/PMC11435807
Researchers investigated cell-free DNA (cfDNA) as a potential biomarker to detect colic in humans. In horses, colic is a life-threatening gastrointestinal (GI) condition. Measurements of cfDNA released from damaged or dying cells in the blood of male and female horses with colic were compared across groups based on GI disease type, signs of inflammation, and survival status. Elevated cfDNA levels were prominent in horses with systemic inflammation, but did not significantly differ by GI disease type or survival. This study suggests that cfDNA may be linked to inflammatory responses in colic conditions. Supported by ORIP (T32OD011130).
A Comparative Review of Cytokines and Cytokine Targeting in Sepsis: From Humans to Horses
Hobbs et al., Cells. 2024.
https://pubmed.ncbi.nlm.nih.gov/39273060
Bacterial infections resulting in endotoxin or exotoxin exposure can lead to sepsis because of dysregulated host responses. Sepsis causes organ dysfunction that can lead to death if not treated immediately, yet no proven pharmacological treatments exist. Horses can serve as a comparative and translational model for sepsis in humans because both species share mechanisms of immune response, including severe neutropenia, cytokine storms, formation of neutrophil extracellular traps, and decreased perfusion. Research on sepsis has focused on the pathophysiological role of interleukin-6, interleukin-1β, tumor necrosis factor-α, and interleukin10. Research on novel sepsis therapies has focused on monoclonal antibodies, cytokine antagonists, and cytokine removal through extracorporeal hemoperfusion. Future sepsis research should focus on optimizing therapeutic strategies of cytokine modulation and analyzing the underlying mechanisms of cytokine dysregulation. Supported by ORIP (T32OD011130).
Temperature-Dependent Alterations in the Proteome of the Emergent Fish Pathogen Edwardsiella piscicida
Jacobsen et al., Journal of Fish Diseases. 2024.
https://pubmed.ncbi.nlm.nih.gov/39304982
Reported outbreaks of Edwardsiella piscicida, a bacterial pathogen among cultured and wild fish, have been steadily increasing over the past decade in tandem with climate change–mediated increases in water temperatures. The capacity for this increasingly prevalent fish pathogen to infect and cause disease in mammals is important to understand. Researchers examined the role of temperature on the virulence of E. piscicida to understand its pathogenesis in the context of climate warming trends and better understand its zoonotic potential. Findings revealed downregulation of virulence-related proteins, such as flagellar and Type VI secretion system proteins, at colder temperatures. These findings highlight the potential environmental factors influencing the pathogen’s threat to aquaculture and public health. Supported by ORIP (S10OD026918, T32OD011147).
Large Animal Models Enhance the Study of Crypt-Mediated Epithelial Recovery From Prolonged Intestinal Ischemia Reperfusion Injury
McKinney-Aguirre et al., American Journal of Physiology-Gastrointestinal and Liver Physiology. 2024.
https://pubmed.ncbi.nlm.nih.gov/39404771/
Intestinal ischemia and reperfusion injury (IRI) is a severe pathological alteration that compromises the intestinal epithelial barrier, causing bacterial translocation, shock, sepsis, and potentially death. Preclinical research for IRI has focused on utilizing murine models, but mice demonstrate key anatomical and physiological intestinal differences from humans, such as tissue enzymes, intestinal permeability, and hypoxic response pathways. The researchers compared a 3-hour IRI porcine model to a 3-hour IRI murine model to reveal which demonstrated a stronger translational capacity. Both models demonstrated crypt damage, but only the porcine model showed recovery-associated crypt death expansion and re-epithelialization. At 72 hours post-IRI, mouse mortality was 84.6%, whereas porcine mortality was 0%. A porcine model would be more reliable for future translational studies focused on understanding IRI mechanisms for diagnosis and therapy advancements. Supported by ORIP (T32OD011130, K01OD010199, R03OD026598) and NIDDK.
Alterations in Tumor Aggression Following Androgen Receptor Signaling Restoration in Canine Prostate Cancer Cell Lines
Vasilatis et al., International Journal of Molecular Sciences. 2024.
https://pubmed.ncbi.nlm.nih.gov/39201315
Prostate cancer (PCa) ranks second worldwide in cancer-related mortality, but only a few animal models exhibit naturally occurring PCa that recapitulates the symptoms of the disease. Neutered dogs have an increased risk of PCa and often lack androgen receptor (AR) signaling, which is involved in upregulating tumorigenesis but can also suppress aggressive cell growth. In this study, researchers sought to understand more about the role of AR signaling in canine PCa initiation and progression by restoring AR in canine PCa cell lines and treating them with dihydrotestosterone. One cell line exhibited AR-mediated tumor suppression; one cell line showed altered proliferation (but not migration or invasion); and a third cell line exhibited AR-mediated alterations in migration and invasion (but not proliferation). The study highlights the heterogeneous nature of PCa in dogs and humans but suggests that AR signaling might have therapeutic potential under certain conditions. Supported by ORIP (T32OD011147).
A Novel TGFβ Receptor Inhibitor, IPW-5371, Prevents Diet-induced Hepatic Steatosis and Insulin Resistance in Irradiated Mice
Szalanczy et al., Radiation Research. 2024.
https://pubmed.ncbi.nlm.nih.gov/38772553
Radiation damages adipose progenitor cells and increases liver fibrosis, leading to the development of metabolic-associated fatty liver disease (MAFLD) and insulin resistance. As the number of cancer survivors increases and the risk of accidental radiation exposure rises, there is a pressing need to characterize and mitigate the delayed effects of radiation exposure. Some of these effects are mediated by TGFβ pathway signaling, which increases in response to radiation exposure and causes fibrosis. In this study, IPW-5371—a small-molecule inhibitor of a TGFβ receptor called activin receptor-like kinase 5 (ALK5)—was shown to protect mice from the effects of sublethal whole-body irradiation and chronic consumption of a Western diet. Mice treated with IPW-5371 exhibited lower fibrosis and fat accumulation in the liver, were more responsive to insulin, and had lower circulating triglycerides and better muscle endurance. IPW-5371 is a promising treatment for mitigating the metabolic effects of radiation exposure and preventing MAFLD. Supported by ORIP (T35OD010946, T32OD010957).
Time of Sample Collection Is Critical for the Replicability of Microbiome Analyses
Allaband et al., Nature Metabolism. 2024.
https://pubmed.ncbi.nlm.nih.gov/38951660/
Lack of replicability remains a challenge in microbiome studies. As the microbiome field moves from descriptive and associative research to mechanistic and interventional studies, being able to account for all confounding variables in the experimental design will be critical. Researchers conducted a retrospective analysis of 16S amplicon sequencing studies in male mice. They report that sample collection time affects the conclusions drawn from microbiome studies. The lack of consistency in the time of sample collection could help explain poor cross-study replicability in microbiome research. The effect of diurnal rhythms on the outcomes and study designs of other fields is unknown but is likely significant. Supported by ORIP (T32OD017863), NCATS, NCI, NHLBI, NIAAA, NIAID, NIBIB, NIDDK, and NIGMS.
Controlled Stiffness of Direct-Write, Near-Field Electrospun Gelatin Fibers Generates Differences in Tenocyte Morphology and Gene Expression
Davis, Journal of Biomechanical Engineering. 2024.
https://pubmed.ncbi.nlm.nih.gov/38529730/
Tendinopathy is associated with mobility issues, and the cell–matrix interactions involved in the development of tendinopathy are not fully understood. In this study, researchers fabricated micron-scale fibrous scaffolds that mimic native collagen fiber size and orientation. They reported that matrix metalloproteinase and proteoglycans (possible indicators of tendinopathy) were more upregulated in the presence of high-stiffness fibers than low-stiffness fibers. The authors’ findings suggest that scaffolds can serve as in vitro models for tendinopathy. Additionally, their work suggests that matrix mechanical properties contribute to cell–matrix interactions during tendinopathy formation. Supported by ORIP (T32OD011130) and NIA.
Ultrasoft Platelet-Like Particles Stop Bleeding in Rodent and Porcine Models of Trauma
Nellenbach et al., Science Translational Medicine. 2024.
https://www.science.org/doi/10.1126/scitranslmed.adi4490
Platelet transfusions are the current standard of care to control bleeding in patients following acute trauma, but their use is limited by short shelf life and limited supply. Immunogenicity and contamination risks also are a concern. Using ultrasoft and highly deformable nanogels coupled to fibrin-specific antibody fragments, researchers developed synthetic platelet-like particles (PLPs) as an alternative for immediate treatment of uncontrolled bleeding. They report that PLPs reduced bleeding and facilitated healing of injured tissue in mice, rat, and swine models (sex not specified) for traumatic injury. These findings can inform further translational studies of synthetic PLPs for the treatment of uncontrolled bleeding in a trauma setting. Supported by ORIP (T32OD011130) and NHLBI.