Department Of Defense Research Articles

Comparison of Tobacco Product Prices at Fort Liberty Army Installation and Surrounding Community Areas, 2021.

High rates of tobacco use persist in the U.S. military, with 18.4% of service members smoking cigarettes in 2018. The Department of Defense's (DoD) 2017 policy required that tobacco retailers on military installations set tobacco product prices equal to the most common community price, including tax, but there is limited evidence confirming whether local retailers are adhering to this policy. We examined tobacco product pricing in tobacco retailers on- and off-post at the largest U.S. Army installation, Fort Liberty, and Cumberland County, North Carolina. Between June and August 2021, we collected data on tobacco product availability, price, and promotions from retailers on Fort Liberty (n = 14) and a random sample of off-post retailers within 10 miles of installation gates (n = 52). We calculated the mode, mean, and median price of each product, plus the difference in these prices at on- and off-post retailers. We used Welch's t-test to test differences in mean prices between on- versus off-post retailers. The mode, mean, and median prices of cigarette packs and cartons were lower on-post than off-post (eg, $0.51-$0.55 cheaper for Marlboro cigarette packs on-post). However, the mode, mean, and median prices of smokeless tobacco products and little cigars were higher on-post than off-post (eg, $0.82-$0.89 more costly for Swisher Sweets 2-packs on-post). Results highlight the need for continued enforcement to ensure compliance with the 2017 DoD policy. Comprehensive policy action to reduce tobacco price disparities on- and off-post is critical to reducing high rates of tobacco use among service members. Despite the implementation of the 2017 DoD pricing policy, some tobacco products remain cheaper at tobacco retailers on-post compared to off-post retailers. Our results highlight the need for greater routine surveillance to increase implementation of the policy-particularly for cigarettes-to reduce high rates of tobacco use among service members.

Contractual Diversification Advantage: A Relational View of the Link Between Supplier Diversification and Performance

Contractual Diversification Advantage: A Relational View of the Link Between Supplier Diversification and Performance

Challenges and opportunities on the horizon of post-quantum cryptography

Large quantum computers have the potential to break many cryptographic systems, e.g., Rivest–Shamir–Adleman, Diffie–Hellman key exchange, and the elliptical curve cryptosystem. The Department of Defense (DoD) is aware of this threat, and the National Institute of Standards and Technology is preparing a set of approved encryption and signature schemes that are not susceptible to these attacks by quantum computers, the so-called Post-Quantum Cryptography (PQC). The task of substituting older encryption and signature schemes raises a number of questions, to which there are not yet clear answers. In this research, we investigate the transition to PQC on existing networks, explain the approved PQC schemes, describe the likely path to an adaptation of PQC, and offer forward guidance on challenges and threats that may be encountered in the process of transition to PQC. This paper discusses the impacts of the new PQC schemes on network performance and speculates on possible side-channel attacks on the new encryption scheme. This paper offers hardware/software solutions based on the Split-protocol.

Exploring over a decade of systems engineering research center: A community detection and text analytics approach

AbstractThe Systems Engineering Research Center (SERC) is a University Affiliated Research Center (UARC) of the US Department of Defense (DoD) formed in 2008 with more than 20 collaborator universities in the United States. Over the last decade, SERC has conducted research with Principal Investigators from universities within the SERC network, as reflected in technical reports (TR). These reports describe detailed information and analysis of the conducted research for every project under SERC support, such as written records of experiments or results of a scientific project. We analyzed the TRs from 2009 to early 2023 to identify research streams, topics, and evolution in systems engineering (SE) research using text mining and network analysis techniques, such as Louvain Community Detection and word similarity. As a result, we identified four major research streams over a decade of research projects, along with insights about topics and the evolution of SE within this time frame. Finally, we distinguished most profile authors and their most significant collaborations and networks.

The biopolitics of algorithmic governmentality: How the US military imagines war in the age of neurobiology and artificial intelligence

With the objective to predict and pre-empt the emergence of political violence, the US Department of Defence (DoD) has devoted increasing attention to the intersection between neurobiology and artificial intelligence. Concepts such as ‘cognitive biotechnologies’, ‘digital biosecurity’ and large-scale collection of ‘neurodata’ herald a future in which neurobiological intervention on a global scale is believed to come of age. This article analyses how the relationship between neurobiology and AI – between the human and the machine – is conceived, made possible, and acted upon within the SMA programme, an interdisciplinary research programme sponsored by the DoD. By showcasing the close intersection between the computer sciences and the neurosciences within the US military, the article questions descriptions of algorithmic governmentality as decentring the human, and as juxtaposed to biopolitical techniques to regulate processes of subjectivity. The article shows that within US military discourse, new biotechnologies are seen to engender algorithmic governmentality a biopolitical dimension, capable of monitoring and regulating emotions, thoughts, beliefs, and subjectivity on population level, particularly targeting the minds and brains of ‘vulnerable’ populations in the global South.

Health Care Utilization During the First 5½ Years of Authorized Service by Transgender U.S. Service Members (2016-2021).

Purpose: This study examined the utilization of gender-affirming health care by active-duty service members during the initial 5½ years that transgender and gender-diverse (TGD) individuals were authorized to serve in the U.S. military. The aim of this study was to inform policy discussions regarding inclusion of TGD individuals in the military. Methods: We conducted a retrospective cohort study using administrative health care data from the Military Data Repository (MDR). We assessed the association of demographic factors with the utilization of gender-affirming medical and surgical care. We calculated the incidence rate of initial TGD-related encounters and new prescriptions for gender-affirming hormones among Defense Department Service members between July 2016 and December 2021. Results: We identified 2481 service members with an initial health care encounter with an associated TGD-related diagnosis. More than half (53%) of these service members started gender-affirming hormones, and 14% underwent gender-affirming surgery. Mastectomies and hysterectomies accounted for more than 70% of surgeries. Service members made 3.22 initial encounters with a TGD-related diagnosis per 10,000 service members per year, with an overrepresentation of service members who were designated female in the MDR (8.62), junior enlisted (4.98), and young (4.64). Individuals designated female in the MRD comprised 17% of all service members but accounted for 46% of initial encounters, 51% of new prescriptions, and 73% of surgeries. Conclusion: The study revealed a higher-than-expected number of service members seeking gender-affirming care, particularly among service members designated female in the MDR. Military Health System clinicians provided most of this care, which may mitigate the cost of delivering this essential medical care.

Abstract PO5-27-02: A Tumor Emboli Platform for Morphometric Analysis, Drug screening and for Intravital Optical Imaging in a Murine Model to Simulate Clinicopathological Features of Inflammatory Breast Cancer

Abstract Background: Inflammatory breast cancer (IBC) is distinguished by the presence of tumor emboli, clusters of tumor cells, found within breast parenchyma and dermal lymphatic vessels. These emboli serve as a crucial clinicopathological hallmark, believed to underlie the characteristic diffuse growth pattern and aggressive progression observed in IBC patients, with nearly 30% of patients presenting with metastatic disease at diagnosis. However, the rarity of this cancer and the absence of a solid tumor mass pose challenges in obtaining biospecimens, particularly those with evidence of tumor emboli. To address this pressing need for preclinical models that replicate this distinctive tumor growth pattern, we describe a tumor emboli culture platform that facilitates live imaging, enables compound screening by assessing various phenotypes of the emboli, and permits evaluation of emboli in an in vivo murine model. Methods: The tumor emboli culture system was evaluated for physiological measurements corresponding to dermal lymphatic vessels and subsequently employed to generate tumor emboli from diverse patient-derived cell lines and PDX. Confocal microscopy was employed to characterize cellular information across multiple slices of the tumor emboli. This provided a comprehensive, multi-parametric analysis of single-cell and spheroid phenotypes, including measurements of number, size, shape, and viability of the organoids. Furthermore, we developed imaging algorithms to evaluate phenotypic changes in tumor emboli in response to anti-cancer drug treatment. We also optimized a technique that allows for in vivo tumor emboli implantation including in a transgenic mice with red fluorescent lymphatic vasculature that were surgically implanted with a dorsal skin window chamber. This allowed for intravital optical imaging of the local tumor microenvironment and adjacent skin. Results: Our culture platform enables live imaging of the tumor emboli generated over a span of 7-10 days, maintaining key parameters including kinematic and dynamic viscosity, density along with sheer wall stress within the reported physiological range for lymphatics. Through higher resolution confocal image acquisition and multi-parametric analysis, we conducted particle counting and classification, providing statistically significant insights into the integrity of tumor emboli over time. Additionally, the developed algorithms allowed for quantitative analysis of images from tumor emboli cultures subjected to anti-cancer drugs, revealing disparities in drug efficacy on tumor emboli integrity and dispersion including inter-cluster space within the emboli. Intravital optical imaging, coupled with quantitative analysis of dispersion characteristics of the tumor emboli implanted in the murine model over 5-6 days, demonstrated a diffuse spread reminiscent of observations in IBC patients. Furthermore, immunohistochemistry staining showed marked Ki67, CD45, F4-80 revealing a proliferative tumor microenvironment with high levels of macrophage infiltration. Conclusions: As of now specific targeted therapies for IBC patients remain elusive. Our culture platform for tumor emboli, when combined with advanced imaging techniques both in vitro and in vivo and traditional approaches like immunohistochemistry and genomic evaluation, forms a powerful toolkit for assessing the phenotype and dispersion characteristics of this unique pathological feature in IBC. This preclinical model offers crucial insights, potentially paving the way for precision medicine strategies in the treatment of this understudied cancer. Funding in part from American Cancer Society Mission Boost MBG-20-141-01-MBG grant (GRD), Department of Defense W81XWH-20-1-0153 (GRD), Duke Consortium for Inflammatory Breast Cancer Education (AB, CW, RE). Citation Format: Dorababu Sannareddy, Theresa Charity, Alexandra Bennion, Caroline Way, Edwin Yu, Ralph Erdmann, Gregory M Palmer, Gayathri R Devi. A Tumor Emboli Platform for Morphometric Analysis, Drug screening and for Intravital Optical Imaging in a Murine Model to Simulate Clinicopathological Features of Inflammatory Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-27-02.

Abstract PO2-17-12: Phase I Trial of alpha-lactalbumin vaccine in high risk operable triple negative breast cancer (TNBC) and patients at high genetic risk for TNBC

Abstract Background: Triple-negative breast cancer (TNBC) has a poor prognosis and may be associated with germline mutations. α-Lactalbumin (aLA) is expressed in lactating breasts but not at other times or in other tissues. Expression of aLA is found in 70% of TNBC (PMID: 27322324) so could be an immunologic target for TNBC based on the “retired protein hypothesis” (PMID: 31926646). In pre-clinical studies, vaccination with aLA provided protection from development of autochthonous tumors in transgenic murine models of breast cancer and inhibited growth of established 4T1 transplantable breast tumors in BALB/c mice (PMID: 20512124). Methods: To determine the safety and immunogenicity of aLA, patients with early stage TNBC are being entered in a Phase I trial of aLA with GMP-grade zymosan adjuvant in Montanide ISA 51 VG vehicle. Subjects receive 3 vaccinations given once every 2 weeks. Events of Common Terminology Criteria for Adverse Events (CTCAE) grade ≥ 2 are considered dose-limiting toxicities (DLTs). Results: CTCAE toxicity by dose level is summarized below. All DLTs were injection site reactions, with ulceration and need for incisional drainage representing the grade 3 events. Seven (7) of 10 patients assayed to date have met protocol specified definitions of an immune response based on ELISpot assays to determine frequencies of T cells producing IFNγ and IL-17 in response to recombinant aLA. Assays for an additional 6 patients will be available in September 2023. Conclusion: Dose level ≤ 2 appears to be the maximum tolerated dose. Based on immune response, additional intermediate dose levels may be studied. An additional cohort of patients receiving concurrent anti-PD1 treatment is being accrued. Accrual of patients with BRCA1/2 or PALB2 mutations planning to undergo prophylactic mastectomy is beginning in order to define the toxicity and immunologic effects in this group and to determine whether inflammatory changes from occult lactational foci will be produced. Funding Source: Department of Defense (W81XWH-17-1-0592 and W81XWH-17-1-0593) Table 1 Worst Toxicity by Dose Level Citation Format: Justin Johnson, Emily Rhoades, Holly Levengood, Halle Moore, Megan Kruse, Erin Roesch, Jame Abraham, Brenna Elliott, Rachel Swartz, Holly Pederson, Elena Haury, Azka Ali, Tiffany Onger, Andrew Sciallis, Zahraa Al-Hilli, Wei Wei, Thaddeus Stappenbeck, George Budd. Phase I Trial of alpha-lactalbumin vaccine in high risk operable triple negative breast cancer (TNBC) and patients at high genetic risk for TNBC [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-17-12.

Oncogenic GNAS drives a pyloric-type transcriptomic program in pancreatic intraepithelial papillary mucinous neoplasms

BACKGROUND & AIMS: Intraductal Papillary Mucinous Neoplasms (IPMNs) are cystic lesions of the pancreas which can serve as precursors for pancreatic ductal adenocarcinoma (PDAC). Recently, we showed that acinar to ductal metaplasia (ADM), an injury repair program associated with pancreatic tumorigenesis, is characterized by a pyloric-type transcriptomic program similar to gastric spasmolytic polypeptide expressing metaplasia (SPEM), suggesting common mechanisms of reprogramming between the stomach and pancreas. The aims of this study were to assay IPMN for SPEM markers and to identify molecular drivers of this program. METHODS: Published RNA-seq studies of IPMN were assessed for SPEM markers, which were validated by immunostaining in patient samples. Murine cell lines expressing KrasG12D +/- GNASR201C were manipulated to identify distinct and overlapping transcriptomic programs driven by each oncogene. A PyScenic-based regulon analysis was performed to identify drivers of SPEM in the pancreas. Expression of candidate drivers was evaluated in patient samples by RNA-seq and immunostaining and a role for SPDEF was investigated. RESULTS: SPEM markers were identified in human IPMN. GNASR201C drove expression of these markers in murine cell lines and siRNA targeting of GNASR201C or KrasG12D demonstrates that GNASR201C amplifies a mucinous phenotype. Regulon analysis identified a role for transcription factors SPDEF, CREB3L1, and CREB3L4, which are expressed in patient samples. CONCLUSIONS: De novo expression of a pyloric-type/SPEM phenotype has been identified in pancreatitis, oncogenic KrasG12D-driven pancreatic neoplasia, and in KrasG12D;GNASR201C-driven IPMN, suggesting common mechanisms of reprogramming between these lesions and the stomach. IPMN-specific GNASR201C drives a SPEM phenotype characterized by the formation of mucus producing cells at the expense of other lineages. AMR was supported by NIH T32GM139400. AM is supported by the MD Anderson Pancreatic Cancer Moon Shot Program, the Sheikh Khalifa Bin Zayed Al-Nahyan Foundation and NIH (U01CA200468, U54CA274371, U24CA274274, R01CA220236). M.C.B.T is supported by a Vanderbilt Digestive Disease Research Center Pilot and Feasibility Grant (P30 DK058404) and a Nikki Mitchell Foundation Pancreas Club Seed Grant. M.C.B.T and N.J. are supported by The Department of Defense (DOD W81XWH2211121-1). The DelGiorno laboratory is supported by the Vanderbilt Ingram Cancer Center Support Grant (NIH/NCI P30 CA068485), the Vanderbilt-Ingram Cancer Center SPORE in Gastrointestinal Cancer (NIH/NCI 5P50 CA236733), the Vanderbilt Digestive Disease Research Center (NIH/NIDDK P30 DK058404), an American Gastroenterological Association Research Scholar Award (AGA2021-13-02), NIH/NIGMS R35 GM142709, The Department of Defense (DOD W81XWH2211121), The Sky Foundation, Inc (AWD00000079), and Linda’s Hope (Nashville, TN). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

A pathway to precision medicine: coronary and cerebral arterial transcriptomic analysis reveals distinct pathophysiological adaptations in two clinically relevant porcine models of heart failure

Traditional treatments for heart failure (HF) with reduced ejection fraction (HFrEF) are ineffective at treating HF with preserved ejection fraction (HFpEF), establishing a need for more targeted therapeutic approaches. To date, the comparative vascular adaptions induced by these two distinct forms of HF have been largely unexplored. Therefore, the objective of this study was to compare HFrEF and HFpEF pathophysiological adaptions in both coronary and cerebral microvasculature in two clinically relevant swine models of HF. We hypothesized that HFrEF and HFpEF will induce differing pathophysiological adaptations within the microvasculature of the heart as well as peripheral tissues, such as the brain. Intact female Ossabaw swine (2 months old) were fed a Western Diet for 4 months to develop metabolic syndrome (HOMA-IR: HFrEF 2.94 ± 0.34; HFpEF 2.95 ± 0.59). At 6 months of age, animals were either subjected to 90 minutes ischemia followed by reperfusion (I/R) to induce a myocardial infarction (MI) recapitulating cardiometabolic HFrEF (38.0 ± 3.9% EF) or were aortic banded to induce pressure-overload with relevance to cardiometabolic HFpEF (61.5 ± 1.7% EF). Following humane euthanasia, coronary arterioles (139.5 ± 4.9 μm inner diameter) and middle cerebral artery second order pial arterioles (281.1 ± 16.7 μm) from each model were dissected and either cannulated and pressurized for myography experiments or flash frozen for RNA isolation, sequencing, and predictive pathway analysis. Smooth muscle dependent U46619 (thromboxane A2 agonist)-induced constriction of cerebral arterioles was not different between groups (HFrEF 46.9 ± 10.3%; HFpEF 50.7 ± 4.8%), however, smooth muscle dependent dilation to sodium nitroprusside (SNP, nitric oxide mimetic) was significantly reduced in HFrEF (37.1 ± 14.0%) compared to HFpEF (83.6 ± 4.6%), suggesting the dilatory capacity of peripheral vessels is impaired when EF% is reduced. Furthermore, RNA-sequencing comparison between HFrEF and HFpEF uncovered 35 differentially expressed genes in the coronary (n=3) and 23 differentially expressed genes in cerebral (n=3) arterioles (q ≤ 0.1). Ingenuity pathway analysis predicted upstream regulators that code for angiotensinogen, STAT3, and interferon-Ƴ were inhibited (z-score > -2.0) in the HFrEF model, which was associated with decreased proliferation of smooth muscle cells and vasculogenesis with increased organismal death and inflammation in the coronary arterioles. Furthermore, analysis of the cerebral arterioles predicted inhibition of angiotensinogen (z-score > -2.0) in the HFrEF model which was associated with increased fibroblast cell death, dedifferentiation of smooth muscle cells, and recruitment of macrophages. Together, these data reveal distinct pathophysiological functional and transcriptomic adaptions between HFrEF and HFpEF in the coronary and cerebral arterioles. Additionally, these data provide three candidate genes that regulate these pathophysiological processes and could be targeted for potential therapeutic intervention. Funding: REGENCOR and Department of Defense (DOD) W81XWH-18-1-0179. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Low Intensity Renal Ultrasound Exposure Reduces Systemic Inflammation Induced by LPS Challenge in Mice

Low-intensity pulsed ultrasound (LIPUS), a procedure historically used to stimulate bone healing and tissue repair, activates the splenic cholinergic anti-inflammatory pathway and ultimately reduces circulating and tissue-specific pro-inflammatory cytokine release if applied to the kidney prior to renal ischemia/reperfusion injury. We questioned whether LIPUS would be effective in reducing the inflammatory response to lipopolysaccharide (LPS) if exposure occurred as pre- or post-treatment. We hypothesized that LIPUS exposure before an LPS challenge would suppress the subsequent inflammatory response in mice, and that LIPUS exposure after an LPS challenge would be similarly beneficial. Female C57BL/6J mice were randomized into Saline, LPS, LPS/Pre-treatment and LPS/Post-treatment groups at 15 weeks of age. Pre-treated mice were subjected to 20-minute LIPUS exposure while under anesthesia for five consecutive days. On the 6th day, mice were injected with LPS (1 mg/kg dissolved in saline, IP) or saline (100 μL). One hour after LPS injection, post-treated mice were exposed to LIPUS for 20 min. Three hours after LPS or saline injection, all mice were humanely euthanized, and plasma, spleen and kidney were harvested for analysis of proinflammatory cytokines associated with the response to LPS. LPS significantly increased plasma TNF-α (280±37 vs. 0.07±0.00 pg/mL), plasma IL-6 (96124±6688 vs. 425±181 pg/mL), splenic IL-6 (0.77±0.16 vs. 0.17±0.04 pg/μg of protein), and renal cortical IL-6 (0.50±0.07 vs. 0.01±0.00 pg/μg of protein) compared to saline-treated mice (all p<0.05). LIPUS pre-treatment significantly reduced plasma TNF-α (183±15 pg/mL) and plasma IL-6 (63656±8441 pg/mL), without altering splenic and renal cytokines in LPS-treated mice. LIPUS post-treatment lowered plasma IL-6 (47432 ± 1182 pg/mL). In conclusion, five days of LIPUS exposure prior to an LPS challenge effectively reduced circulating inflammatory mediators, while a single LIPUS exposure after an LPS challenge also successfully reduced systemic IL-6. These findings demonstrate the potential in using LIPUS as a therapeutic strategy for quelling acute inflammatory responses and warrant further investigation of its use as a therapy for chronic inflammatory diseases. Studies funded by Department of Defense (LR210096) for KWM. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Cost-benefit analysis with return on investment of clinical pharmacists in the Military Health System.

The Defense Health Agency comprises more than 700 military medical, dental, and veterinary facilities and provides care to more than 9.6 million beneficiaries. As medication experts, pharmacists identify opportunities to optimize medication therapy, reduce cost, and increase readiness to support the Defense Health Agency's mission. The Tripler Pilot Project and the Army Polypharmacy Program were used to establish a staffing model of 1 clinical pharmacist for every 6,500 enrolled beneficiaries. No large-scale cost-benefit study within the military health care system has been done, which documents the number of clinical interventions and uses established cost-avoidance (CA) data, to determine the cost-benefit and return on investment (ROI) for clinical pharmacists working in the medical treatment facilities. To validate the patient-centered medical home staffing model across the military health care system using the Tripler Pilot Project results to provide a cost-benefit analysis with an ROI. The secondary goal is to describe the interventions, staffing levels, and US Department of Defense-specific requirements impacting the provision of clinical pharmacy. A retrospective analysis of 3 years of encounters by clinical pharmacists in which an intervention was documented in the Tri-Service Workflow (TSWF) form as part of the electronic health record was completed. The analysis used 6 steps to assign CA intervention types and to prevent duplication and overestimation of the ROI. The absolute number of clinical pharmacists was determined using workload criteria defined as at least 20 encounters per month for at least 3 months of each calendar year. The number of clinical pharmacist full-time employees (FTEs) was determined by dividing the number of total active months by 12 months. Attrition was calculated comparing the presence of a unique provider identification between calendar years. The ROI range was calculated by dividing the CA by the total cost of clinical pharmacists using the variables' raw and extrapolated CA based on percentage of documentation template usage and the active clinical pharmacist calculation (absolute and FTE-based). Between January 1, 2017, and December 31, 2019, a total of 1,069,846 encounters by clinical pharmacists were documented in the electronic health record. The TSWF Alternative Input Method form was used by pharmacists to document 616,942 encounters. Forty-three percent of TSWF documented encounters had at least 1 CA intervention. The absolute number of clinical pharmacists associated with a documented encounter in any medical treatment facility ranged from 404 in 2017 to 374 in 2018 and the clinical pharmacist FTEs ranged from 324 in 2017 to 314 in 2019. Annual attrition rates for clinical pharmacists ranged from 15% to 20% (58 to 81 clinical pharmacists) annually. The total CA range was $329,166,543-$534,014,494. The ROI range was between $2 and $4 per dollar spent. This analysis demonstrated that ambulatory care clinical pharmacists in the Military Health System bring value through a positive ROI. Our study also identified a potential shortage of clinical pharmacists within the Air Force and Navy branches impacting medication management. This can have a negative impact on the readiness of service members, one of the leading priorities of the US Department of Defense.

Cognitive Function, Diet, and Gender are Associated with Unique Microbiome Signatures in Cancer Survivors

Despite the development of new and highly effective cancer therapies, emerging evidence suggests that these treatments are associated with long-term side effects, which may contribute to cognitive impairment (CI) or dementia in cancer survivors. Many of these side effects are linked to gut health and a perturbed gut microbiome. However, the role of the gut microbiota in cancer treatment-related side effects, especially in older adults, remains largely unknown. Furthermore, it remains elusive how other factors, such as diet and gender, may impact gut microbiota. We hypothesize that cancer survivors have a distinct microbiome signature compared to non-cancer controls and that CI, diet, and gender are associated with unique microbiomes in survivors. Here, we analyzed the gut microbiome (using whole genome sequencing) and cognitive function (using the Montreal Cognitive Assessment [MoCA]) of 150 older adults (≥ 60 years) from the MiaGB (Microbiome in aging Gut and Brain) consortium. We first assessed microbiome signatures of cancer survivors in our cohort compared to non-cancer controls. We show that the gut of cancer survivors is significantly enriched with Escherichia, Eggerthella lenta, and Lachnospiraceae bacterium OF09 33XD. Next, participants were further stratified based on MoCA score, diet (yogurt/probiotic consumption), and gender and we assessed their microbiota. E. lenta and L. bacterium OF09 33XD remained enriched in cancer survivors when separating based on all three of these factors. We also found that cognitive function, yogurt/probiotic use, and gender were linked with unique microbiome signatures in cancer survivors. Interestingly, the abundances of two well-studied probiotics, Streptococcus thermophilus and Lactobacillus rhamnosus, were significantly low in cancer survivors with CI. Additionally, increased S. thermophilus abundance was positively correlated with MoCA score (Spearman p = 0.054, r = 0.159). Our results indicate that older adult cancer survivors harbor a unique gut microbiome, which could also be impacted by cognitive function, yogurt/probiotic consumption, and gender. Elucidating how these factors modulate the microbiome, independently and together, will aid in the development of novel and precision microbiome-based therapies to combat cancer treatment-related side effects in survivors. We would like to thank the Ed and Ethel Moore Alzheimer’s Disease Research Program of the Florida Department of Health (22A17), the National Institutes of Health, National Institute of Aging (R56AG069676, R56AG064075, RF1AG071762, R21AG072379, U01AG076928), and the Department of Defense (W81XWH-18-PRARP AZ180098) for funding support. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

NSAIDs do not influence exercise effects on muscle size in rats or muscle protein synthesis signaling in humans

BACKGROUND: The aim of this project was to determine the impact of non-steroidal anti-inflammatory drugs (NSAIDs) on skeletal muscle adaptations to exercise. NSAIDs possess analgesic and anti‐inflammatory properties that occur by blocking cyclooxygenase (COX) enzymes, thereby inhibiting the production of prostaglandins. In the first study, we determined if low-dose chronic NSAID use affects muscle size in rodents exercising for six weeks. In the second study, we determined if a single high dose of NSAIDs effects the muscle protein synthetic signaling response to a bout of plyometric exercise. Our hypotheses were that NSAIDs would reduce both muscle size and muscle protein synthesis (MPS) signaling. METHODS: Study 1: 9-wk-old male Wistar rats (n=80) were randomized to placebo (PLA), naproxen (NAP), ibuprofen (IBU), or flurbiprofen (FLU) with or without exercise (EX) for six weeks. Exercise consisted of treadmill running at 25 m/min, for 30 minutes per day, five days per week. Soleus muscle was stained for myosin heavy chain (MHC) I or MHC IIA then analyzed for cross sectional area (CSA) and fiber type percentage. Rodent data were analyzed using a one-way ANOVA. Study 2: In a randomized, counter-balanced order, 12 participants (2 females, 10 males), performed four independent plyometric exercise bouts consisting of 10 sets of 10 plyometric jumps at 40% of their 1RM, separated by a minimum of one week. Prior to each session, participants consumed a single dose of celecoxib (CEL 200 mg), IBU (800 mg), FLU (100 mg) or PLA. Muscle biopsies were collected before (PRE) and 3-hours post (POST) exercise. Muscle was analyzed via immunoblot for the following: phospho(p)-AKT(S473), total AKT, p-mTOR (S448), total mTOR, p-S6 (S235/236), total S6, p-4EBP1, and total 4EBP1. Fold changes were calculated from PRE to POST. Data were analyzed using a repeated measures ANOVA. All data are presented as mean ± SD. RESULTS: Study 1: There was no significant difference (p<0.05) in muscle CSA (PLA: 4060±517; PLA+EX: 3965±605; IBU: 3720±804; IBU+EX:4129±477; FLU: 3743±671; FLU+EX: 3649±541; NAP: 4157±1011; NAP+EX: 4123±586) or MHC IIA percentage (PLA: 10±7; PLA+EX: 10±5; IBU: 7±5; IBU+EX:9±3; FLU: 11±4; FLU+EX: 11±6; NAP: 11±4; NAP+EX: 12±3) between groups. Study 2: There was no significant difference (p<0.05) in fold-change between groups for p-AKT/total AKT (PLA: 1.23±0.4; IBU: 1.13±0.3; CEL: 1.26±0.4; FLU: 1.31±0.4), p-mTOR/total mTOR (PLA: 1.21±0.2; IBU: 1.21±0.3; CEL:1.34±0.2; FLU: 1.49±0.3), p-S6/total S6 (PLA: 11.48±10.6; IBU: 10.9±6.8; CEL: 6.01±2.98; FLU: 25.25±19.38), or p-4EBP1/total 4EBP1 (PLA: 1.71± 1.35; IBU: 1.23±0.98; CEL: 1.07 ±0.64; FLU: 2.03±1.49). CONCLUSION: Chronic low-dose NSAID consumption does not influence muscle size or MHC in exercising rodents. Similarly, an acute high dose of an NSAID does not affect the MPS signaling response in exercising humans. Funding was provided by the Military Operational Medicine Research Program. The opinions or assertions contained herein are the private views of the author(s) and are not to be construed as offcial or as reflecting the views of the Army or the Department of Defense. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Enhancing Sarcolemmal Membrane Repair Using a Novel Protein Therapeutic Approach can Improve Membrane Integrity in Duchenne Muscular Dystrophy Cells and Mouse Models

Duchenne Muscular Dystrophy (DMD) is a fatal neuromuscular disease involving progressive cardiac and skeletal myocyte cell death and subsequent muscle degeneration. DMD and Becker muscular dystrophy (BMD) result from mutations in the dystrophin gene that compromise the structural integrity of the sarcolemma. While there has been important recent progress in the treatment of DMD, the currently available therapeutics have significant limitations. Thus, novel therapies that address the compromised sarcolemmal membrane integrity are an unmet medical need. Tripartite motif protein 72, or mitsugumin 53 (TRIM72/MG53), facilitates the sarcolemma repair response after disruption of the membrane. Loss of TRIM72/MG53 function in mice leads to a progressive myopathy. Exogenous delivery of recombinant human MG53 protein (rhMG53) can increase sarcolemmal membrane repair in many different cell types and ameliorate pathology in models of DMD and multiple limb girdle muscular dystrophies. Despite the promise of rhMG53 as a therapeutic invention the development of this protein to treat DMD has been complicated by findings showing that high levels of the protein correlate with metabolic dysfunction in animal models and some human patients. Deletion analysis of the major domains of the rhMG53 protein allowed us to design an improved version of rhMG53 called MyoTRIM. MyoTRIM contains amino acid replacements to eliminate metabolic effects and improve solubility while maintaining membrane repair effects. One set of modifications inactivate the E3 ligase activity of the protein, which revealed this function is dispensable for subcellular localization of the protein. TRIM72/MG53 is reported to mediate this effect by binding phosphatidylserine (PS) at membrane injury sites, so we demonstrate that MyoTRIM can bind PS-coated beads to illustrate that carboxy-terminal domains are required for effcient PS binding rather than the E3 ligase function. External application of MyoTRIM can increase membrane repair capacity in a variety of cell-based assays using DMD and BMD patient myoblasts and myotubes. We also establish that MyoTRIM can increase membrane repair and prevent eccentric contraction induced injury in a dystrophin deficient mouse model. Taken together, these results provide mechanistic insight into rhMG53 function and indicate that MyoTRIM can recapitulate the therapeutic effects on sarcolemmal membrane repair while eliminating E3 ligase activity and associated side effects. This work was supported by the Offce of the Assistant Secretary of Defense for Health Affairs through the Duchenne Muscular Dystrophy Research Program (DMDRP) under Translational Research Award HT9425-23-1-0940. The opinions, interpretations, conclusions, and recommendations are those of the author and are not necessarily endorsed by the Department of Defense. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Specific Microbiome Signature Dynamics Could Predict Aging Continuum and Cognitive Impairment in Older Adults

The global population is aging, facing a substantial burden of age-related disorders, including cognitive impairment (CI), Alzheimer's disease (AD), and related dementias (ADRD). The lack of effective strategies for preventing and treating these conditions can be attributed to our incomplete understanding of the biology of aging. Emerging evidence strongly suggests that the gut microbiome plays a pivotal role in aging and its association with cognitive decline and ADRD. Yet, the transformations occurring within the microbiome during the aging continuum remain insuffciently studied. We have addressed these significant knowledge gaps by analysing samples and data from 176 older adults participating in the multi-site Microbiome in Aging Gut and Brain (MiaGB) consortium. Whole-genome metagenomic analysis unveiled distinct microbiome profiles among three aging categories: (i) 60-69 (n=62), (ii) 70-79 (n=78), and (iii) 80+ (n=36), spanning from phyla to species-level phylogeny. Notably, in older adults, changes in the microbiome were observed with respect to the aging continuum and cognitive impairment (CI). The abundance of Lachnospiraceae, Eggerthellaceae, Dorea, Blautia, and Eggerthella decreased, while Veillonellaceae increased in the gut of older adults with CI but not within the aging continuum. Interestingly, only Proteobacteria, Firmicutes, Candidatus melainabacteria, Coriobactericeae, Ruminococcaceae, Anerostipe hadrus, and Collinsella aerofaciens decreased, while Bacteroidetes, Bacteroidiceae, and Bacteroides uniformis increased within the aging continuum but were not impacted in CI sub-groups. However, both Ruminococcus torques and Streptococcus thermophilus decreased with aging continuum and CI. These results indicate unique microbiome changes specific to the aging continuum, as well as distinct changes with CI, independent of age. Thus, they not only hold promise as prognostic markers for assessing the risk of cognitive decline and dementia in older adults but also pave the way for designing precision microbiome interventions to mitigate the risks posed by these debilitating public health issues. We thank the Ed and Ethel Moore Alzheimer’s Disease Research Program, Florida Department of Health (22A17), National Institutes of Health, National Institute of Aging (R56AG069676, R56AG064075, RF1AG071762, R21AG072379, U01AG076928), and Department of Defense (W81XWH-18-PRARP AZ180098) for funding support. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Structure and Function of Pancreatic Neural Circuitry in Obesity and Diabetes

INTRODUCTION: Pancreatic islets are richly innervated by autonomic nerves which contribute to physiological regulation of islet hormone release and blood glucose. Published studies suggest obesity disrupts pancreatic innervation and may contribute to metabolic dysfunction. However, these studies largely rely on 2D imaging of islets and experiments aimed at assessing the function of pancreatic nerves have not been organ specific. Determining how high-fat diet (HFD) impacts pancreatic nerve structure and function using 3D imaging and organ-specific neuromodulation may provide new insights into the pathophysiology of diabetes and identify novel therapeutic approaches to treat diabetes. METHODS: To test the hypothesis that HFD causes structural changes in pancreatic innervation, C57Bl6 mice were randomized to 1, 4 and 12 week high-fat (HFD) or low-fat diet (LFD) groups. Metabolic phenotyping was determined. Pancreata were cleared and immunolabeled using iDISCO+, imaged by lightsheet (4X) and confocal (10X) microscopy and images were analyzed using Imaris software. To test the effects of HFD on pancreatic nerve function, we used AAV8 delivery of cre-dependent neuromodulatory constructs to activate or silence pancreatic parasympathetic or sympathetic nerves. To modulate pancreatic parasympathetic nerves, we delivered cre-dependent hM3D(Gq) for activation, cre-dependent diphtheria toxin A subunit for silencing, or mCherry (control) into the pancreas of Chat-cre mice. To modulate pancreatic sympathetic nerves, we used pancreatic injection of retrograde AAV delivering cre and celiac injection of cre-dependent hM3Gq (activation), hM4Gi (silencing) or mCherry (control). Mice were fed LFD or HFD for up to 12 weeks and the effects of neuromodulation on glucose metabolism were examined. RESULTS: HFD significantly impaired glucose tolerance, insulin sensitivity and altered plasma insulin and glucagon after 1, 4 and 12 weeks of HFD consumption. HFD consumption significantly altered pancreatic neural structure. Within islets, 1 week of HFD significantly increased sympathetic neural volume. With prolonged HFD, there was significant loss of islet parasympathetic innervation. Reproducing loss of islet parasympathetic innervation impaired glucose tolerance but sympathetic activation did not alter glucose metabolism. Targeted silencing of pancreatic sympathetic innervation or activation of pancreatic parasympathetic innervation significantly improved glucose tolerance in hyperglycemic mice fed HFD. CONCLUSION: Short term HFD causes early rapid changes to islet sympathetic nerves while long term HFD consumption results in loss of pancreatic parasympathetic innervation of the islet. The effects of HFD consumption are improved by inhibiting pancreas-projecting sympathetic fibers or through activation of pancreatic parasympathetic nerves. These studies suggest modulating pancreatic innervation may improve glucose control in obesity. NIH F31 Predoctoral Fellowship (1F31DK129016-01A1, R.H.) ISMMS MSTP T32 (GM007280) NIH (R01NS097184, OT2OD024912, S.S.) American Diabetes Association (ADA #1-17-ACE-31, S.S) Department of Defense (W81XWH-20-1-0345, S.S). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

β-Hydroxybutyrate Recapitulates the Beneficial Effects of Time-Restricted Feeding and Periodic Fasting in Multiple Rodent Models of Polycystic Kidney Disease

Polycystic kidney disease is a monogenic disease caused predominantly by mutations in the PKD1 or PKD2 genes. These mutations result in the formation of large fluid-filled cysts derived from kidney epithelial cells that slowly replace functional healthy tissue. Affected kidneys rely heavily on glycolysis to meet energy demands, and is accompanied by a reduction in fatty acid oxidation and mitochondrial function. We previously reported that interventions inducing a state of ketosis, including caloric restriction, time-restricted feeding (TRF), ketogenic diet, extended fasting, and ketone supplementation, ameliorate or reverse polycystic kidney disease progression in multiple animal models. To elaborate on the capability of ketosis to alter disease progression, we compared, head-to-head, the effects of a daily 16:8 TRF regimen to periodic 48-hour fasting (PF) in both juvenile and adult Cy/+ rats. We found that alternative fasting interventions prevent juvenile disease progression and partially reverse established kidney disease in adults. Further, to test our hypothesis that an increase in β-hydroxybutyrate (BHB) may mediate these beneficial effects, we administered BHB to adult Cy/+ rats and stereospecific isomers to two orthologous mouse models of PKD ( P kd1RC/RC, Pkd1-Ksp:Cre). BHB recapitulates the effects of fasting in these models independent of stereoisomer, reducing mTORC1 signaling, increasing GSK-3β phosphorylation, expression and translocation of Nuclear factor erythroid 2-related factor 2 (Nrf2) in cystic epithelia, and subsequent downstream targets of Nrf2. These findings extend and expand our previous report on the beneficial effects of ketosis on cystic disease progression and suggest that ketogenic metabolic interventions and BHB supplementation are capable of metabolic reprogramming in polycystic kidney disease. This work was supported by grants from the NIH (Grants R01DK109563, R01DK124895) and the US Department of Defense (Grant W81XWH2010827) to T.W., and gifts from the Amy P. Goldman Foundation and the Jarrett Family Fund to University of California, Santa Barbara, to support the work of T.W. The MRL Shared Experimental Facilities are supported by the MRSEC Program of the NSF under Award No. DMR 1720256; a member of the NSF-funded Materials Research Facilities Network (www.mrfn.org). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Renal potassium regulation in a pig model of therapeutic hypothermia

Therapeutic hypothermia is increasingly utilized clinically to reduce tissue metabolism and protect against neurological damage in cases of cardiac arrest, traumatic brain injury or perinatal hypoxic ischemia. With even mild exposure to hypothermia, hypokalemia develops purportedly due to transcellular potassium shifts resulting in decreased circulating potassium levels. Renal dysfunction with body temperature cooling has also been postulated to potentially contribute to development of sustained hypokalemia. In this study, we used a pig model of controlled acute hypothermia without confounding hypotension and hypoxemia, to test the hypothesis that renal handling of potassium remains intact in hypothermia and is not the cause of decreased circulating plasma potassium seen with body cooling. Anesthetized, mechanically ventilated Duroc cross young pigs (n=25, body weight = 10.0 ± 0.4 kg, male or female) were catheterized for hemodynamic monitoring, regional blood flow assessment via colored microspheres, and urine collection. After baseline values were obtained, pigs were divided into a control normothermia group (n=12) with body temperature maintained at 38.4 ± 0.1 oC or a hypothermia group (n=13) with core body temperature cooled to 34.5 ± 0.1 oC and hypothermia sustained for 2 hours. Hypothermia reduced tissue metabolism as indicated by a decrease in oxygen consumption (VO2= 5.2 ± 0.2 ml/kg in normothermia vs 3.7 ± 0.3 ml/kg in hypothermia. Mean arterial pressure (68± 3 mm Hg) and cardiac output (199 ± 21 ml/min/kg) were not different between groups. Even with the short duration of cold exposure, plasma potassium was lower (p<0.05) within 2 hours of hypothermia (4.1 ± 0.1 mEq/L) vs control (4.8 ± 0.1 mEq/L). Cold exposure caused redistribution of blood flow to the small intestines from other internal organs. Renal blood flow tended to decrease with cold, but glomerular filtration rate was suffcient to maintain urine flow, sodium excretion and free water clearance. Potassium clearance, however, was lower (p<0.05) in hypothermia (0.70 ± 0.07 ml/min/kg) than in normothermia (1.04 ± 0.07 ml/min/kg), with lower potassium excretion (hypothermia = 2997 ± 331 mEq/min vs control = 4784 ± 393 mEq/min, p<0.05) and fractional excretion of potassium. Reduced renal potassium excretion is consistent with renal compensation for lower circulating potassium induced by hypothermia. Interestingly, with relatively higher blood flow to the small intestines compared to decreased blood flow of other internal organs, potassium secretion in the early colon may contribute to further potassium wasting in hypothermia. The rapid initiation of decreased potassium circulating levels with hypothermia supports the thesis of temperature sensitive cell membrane potassium channels affecting extracellular to intracellular shifts of potassium. Results of this study indicate that renal potassium regulation is maintained in hypothermia and functions to decrease urinary potassium loss in the face of hypokalemia. The views expressed are those of the authors and do not necessarily reflect the offcial policy or position of the Defense Health Agency, Department of the Army, Department of Defense, or the U.S. Government. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Identification of Early Transcriptional Markers of Autosomal Dominant Polycystic Kidney Disease Cystic Epithelial Cells

Study objective: Mechanisms driving autosomal dominant polycystic kidney disease (ADPKD) cystogenesis, a hallmark of this lethal monogenic disease, are not well understood and reliable biomarkers are scarce. We sought to explore transcriptional changes in ADPKD models with suppressed and non-suppressed cystic phenotype to explore mechanisms driving ADPKD cystogenesis and identify potential biomarkers in disease progression. Hypothesis: Early-stage kidneys from a model in which cystic disease is suppressed by expression of the polycystin-1 C-terminal tail (CTT), a 200 amino acid portion of the larger polycystin-1 protein that is dysregulated in ADPKD, exhibit a differential transcriptional profile from early-stage kidneys in a non-suppressed model. Methodology: Orthologous doxycycline-inducible Pkd1fl/fl;Pax8rtTA;Teto-Cre ADPKD C57BL/6N mouse models expressing CTT ( Pkd1-KO+CTT) or not ( Pkd1-KO) were induced between 4-6 weeks and aged to 10 weeks. We performed single cell RNA sequencing (scRNA-seq) with single cell kidney suspensions from biological replicates that were pooled and processed for cDNA synthesis and library preparation with 10X Chromium technology. Reads were aligned using the 10X Genomics CellRanger pipeline and further processed using the gene cell-inverse cell frequency (gf-icf) pipeline. Data: Clusters corresponding to tubule segments were identified using established annotations. Several novel clusters defined by expression of multiple markers, including Jarid2, Tmtc2, and Filip1l, were identified in the Pkd1-KO model. These clusters were sparsely populated in Pkd1-KO+CTT samples, suggesting that they may correspond to cyst epithelial cells that are suppressed by CTT expression. Each of these novel clusters included cells whose markers identified them from distinct tubule segments (e.g. Sglt2, Umod, S100g), suggesting that cells of different segments are clustered together by virtue of sharing the putative cyst cell transcriptional signature. Importantly, at 10 weeks there are no significant differences in disease endpoints such as kidney weight to body weight, serum creatinine, blood urea nitrogen, or kidney morphology between the Pkd1-KO+CTT and Pkd1-KO models, suggesting that the cells assigned to the cystic epithelial cell clusters exhibit early identifiable differences in transcriptional programming. Summary of results: scRNA-seq at an early timepoint reveals novel transcriptional makers of putative cystic epithelial cells. The protein expression levels of individual markers are being assessed. Conclusions: These results suggest that there are epithelial cells early in disease progression exhibiting a unique transcriptional signature that may elucidate the mechanisms of cyst formation and that may provide new candidate biomarkers. This work was funded in part by the NIH F31 DK135356 (VR), NIH RC2 DK120534-01 (MJC), PR191158 Department of Defense (MJC), and PKD 905682 Foundation for Research in Polycystic Kidney Disease Research Grant (MJC). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.