bluuebunny/crossref_metadata_2025_split huggingface dataset:
Autophagy Is Required for Cell Growth and Protein Anabolism in Lung Cancer
Authors: Ryan Patrick , Fluckey James D. 
Published: May 2024

Background: Rampant and unregulated cell growth is a key hallmark of cancer pathology; however, much remains to be discovered about the process that allow for pathological growth in cancerous cells. Recently, we demonstrated that the autophagy-related cysteine protease ATG4B is required for protein anabolism in skeletal muscle, indicating a previously undescribed mechanism by which autophagy directly acts as a recycling/remodeling system for cellular anabolism. Purpose: To investigate if ATG4B is responsible for growth in cancer, and if inhibition of ATG4B is a successful strategy to target cancer growth. Hypothesis: We hypothesized that ATG4B would be higher in cancerous tissues versus healthy ones, and that inhibition of ATG4B by NSC185058 would inhibit cell growth and reduce protein anabolism. Methods: We used the UALCAN web tool to analyze the TCGA data set for differences in ATG4B gene expression in lung adenocarcinoma, comparing healthy to cancerous tissues as well as across cancer stages. Separately, we used the A549 lung cancer cell line as a model to study the effects of ATG4B inhibition, treating cells with 100 μM NSC185058 or equimolar DMSO as a vehicle control, and analyzing treated cells for proliferation and protein synthesis rates. Welch’s t-test was used to calculate differences in TCGA data, while a two-tailed student’s t-test was used to determine differences in proliferation at indicated time points, with an α-level of 0.05. Results: ATG4B expression is 22% higher in cancerous tissues vs healthy controls (p<0.05), and also higher in stages 1-4 of lung adenocarcinoma (Healthy vs Stage 1: +25%, Healthy vs Stage 2: +23%, Healthy vs Stage 3: +13%, Healthy vs Stage 4: +30%, p<0.05). Treatment with NSC185058 suppresses cell growth across 72 hours (24 hour VC vs NSC: -59%, 48 hour VC vs NSC: -83%, 72 Hour VC vs NSC: -90%), and reduces 24-hour rates of protein synthesis by 56% (p<0.05) in cancer cells. Conclusions: ATG4B expression is increased in lung adenocarcinoma, including in early-stage cancer, and inhibition by NSC185058 drastically reduces anabolism in cancerous cells. We posit that autophagy, mediated by ATG4B is required for protein anabolism in lung cancer, and that targeting this process represents a novel strategy to combat cancer pathology. This work was generously funded by the Huffnes Institute and School of Education and Human Development at Texas A&M University. 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.
TAK1 Signaling in Cardiac Fibroblast Contributes to Inflammation Resolution Post Myocardial Infarction
Authors: Nguyen Daniel , Stephan Jonah , Boyd Nolan , Brainard Robert , Hellmann Jason , Wysoczynski Marcin , Hill Bradford 
Published: May 2024

Introduction: Resident cardiac fibroblasts are often defined by their extraordinary capacity to deposit extracellular matrix after cardiac injury; however, fibroblasts also react avidly to pro-inflammatory stimuli, suggesting that they may also be mediators of inflammation. Initially identified as a TGFβ responsive enzyme, TGF-β activated kinase 1 (TAK1) has been shown to be significant in regulating pro-inflammatory signaling in several disease models. The goal of this study was to understand how fibroblasts integrate pro-inflammatory signals to regulate acute inflammation following myocardial infarction (MI). We hypothesize that cardiac fibroblasts utilize a TAK1-dependent mechanism to integrate pro-inflammatory signals and orchestrate the cellular immune response following injury. Methods and Results: To create a fibroblast-specific model for TAK1 knockdown, TAK1 fl/fl mice were bred to Col1a2-CreERT mice. Following 2 weeks of tamoxifen chow feeding, both Cre− and Cre+ TAK1 fl/fl mice underwent permanent coronary ligation to induce MI. Three days following MI, immune cell populations from the heart, spleen, and peripheral blood were evaluated through flow cytometry. Deletion of TAK1 in fibroblasts in vivo diminished neutrophils and Ly6C low patrolling monocytes populations in the heart and decreased the number of CCR2neg resident macrophages after MI (n=10/group; p<0.05). Interestingly, circulating levels of neutrophils in the peripheral blood as well as those in the spleen were not significantly different between the groups. To determine how TAK1 may regulate pro-inflammatory signaling, isolated cardiac fibroblasts from TAK1 fl/fl mice were treated with Ad-CMV-iCre and were subsequently treated with IL1β. Notably, TAK1 knockdown suppressed IL1β-dependent p-JNK and NFκB signaling as well as MMP3 production. Further LC-MS/MS evaluation of lipid mediators in conditioned medium showed that deletion of TAK1 significantly increased fibroblast-derived resolvins (RvE2, RvD1, RvD4, RvE4) and lipoxins (LXA4, 15( R)-LXA4) (n= 3-5; p<0.05). Conclusion: Resident cardiac fibroblasts regulate the acute immune response following MI via a TAK1-dependent mechanism. Secreted factors derived from cardiac fibroblasts likely play a pivotal role in shaping the inflammatory and immune response after MI. NIH and AHA. 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.
The Regulatory Role of microRNA-21 in Coronary Microcirculation in Metabolic Syndrome
Authors: Juguilon Cody , wANG YANG , Enrick Molly , Gadd James , Clark Alyssa , Yanez Katherine , Yin Liya 
Published: May 2024

Coronary vasculature is essential to supply oxygen and nutrients to the heart and maintain normal cardiac function. Obstruction of large vessels of coronaries (atherosclerosis) is well studied, but coronary microvascular dysfunction (CMD), which is associated with diabetic cardiomyopathy, Takotsubo cardiomyopathy, Ischemia with the non-obstructive coronary artery (INOCA), and HFpEF, is understudied. CMD is characterized by impaired endothelial-dependent vasodilation, but detailed mechanisms have yet to be elucidated. The anti-fibrotic role of microRNA-21 (miR-21) is reported in the HFrEF induced by ischemia/reperfusion or pressure overload, but how miR-21 regulates CMD is not entirely understood. Our recent study shows miR-21 ablation ameliorated impaired vasodilation in isolated coronaries of mice fed on high fat and high sugar (HFHS) diet. In this study, we examined the coronary flow reserve (CFR), the relationship between myocardial blood flow (MBF) and cardiac work (doppler) under hyperemia, cardiac function (echocardiography and exercise exertion test), fibrosis and gene expression of miR-21 knockout and wild-type (WT) mice fed on chow or HFHS diet. Our preliminary data show that MBF and CFR were decreased, cardiac index, stroke volume, and running distance were reduced, and the E/E’ ratio was increased in WT mice fed on the HFHS diet compared to the WT mice fed on the chow diet. The perivascular fibrosis was increased in the WT mice fed on the HFHS diet compared to WT mice on the chow diet. The ablation of miR-21 reversed all these changes in the mice treated with HFHS, suggesting miR-21 deficiency ameliorated CMD in metabolic syndrome. Moreover, we used endothelial-specific miR-21 knockout to study the endothelial miR-21 function. Interestingly, the endothelial mi-R21 KO phenocopied the global knockouts, suggesting the benefit of miR-21 deficiency to coronary microvascular function in metabolic syndrome is from endothelial cells. The study provides the potential therapeutic strategy to target vascular endothelial cells with miR-21 antagomir for CMD in metabolic syndromes. AHA 970663,1R56HL165207,1 R01 HL165207-01A1 to LY and 1 F31 HL156726-01A1 to CJ. 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.
Mechanisms of Iron-Mediated Renal Injury in a Mouse Model of Sickle Cell Disease
Authors: Sako Mohammad , Patel Margi , Walker Savannah , Kasztan Malgorzata 
Published: May 2024

Background: Sickle cell disease (SCD) is a hematologic disorder characterized by polymerization of the mutated hemoglobin S and sickling of red blood cells, leading to hemolysis, release of free heme/iron, and subsequent tissue iron accumulation. The kidney is one of the most frequently affected organs by iron overload, and chronic hemolysis is associated with chronic kidney disease severity in SCD. The potential role of iron overload in causing the observed renal injury in SCD has never been established. The goal of our study is to identify the impact of iron accumulation on the renal phenotype in SCD. We hypothesized that renal iron accumulation causes injury by oxidative stress dependent ferroptosis and/or mitochondrial dysfunction and subsequent kidney damage, that is worse in males than in females. Methods: We used 20-week-old male and female humanized SCD mice (HbSS) and age-matched genetic controls (HbAA). Mice were treated with either vehicle or the iron chelator Deferiprone (DFP, 100 mg/kg/day) for 8 weeks. Urinary excretion of protein and albumin as markers of renal injury were measured. Glomerular filtration rate (GFR) was measured transdermally after injection of FITC-sinistrin. Thiobarbituric acid reactive substance (TBARS) assay was performed for assessment of lipid peroxidation. Mitochondrial bioenergetics was assessed by Oroboros O2k Fluorometer of permeabilized renal cortices. Results: We previously demonstrated comparable iron accumulation in the kidney of male and female mice. However, HbSS males developed a more severe renal injury than females at 20 weeks of age, evidenced by proteinuria (2.52 ± 0.16 vs. 0.55 ± 0.16 mg/24hrs, p=0.0008) and albuminuria (76.44 ± 6.85 vs. 33.9 ± 8.81 μg/24hrs, p=0.0005). There was higher lipid peroxidation, a hallmark of ferroptosis, in the renal cortex of female HbSS than HbAA mice (1.31 ± 0.07 vs. 1.07 ± μM/mg, p=0.04). Bioenergetics studies revealed significantly lower state 3 oxygen consumption rate (108.2 ± 18.1 vs 164.8 ± 9.3 pmol/(s*mg), p=0.05), signifying lower oxidative phosphorylation capacity in HbSS males. In addition, there was significant reduction in state 4◦ respiration (36.4 ± 3.4 vs. 52.8 ± 3.4 pmol/(s*mg), p=0.03) in male HbSS mice. I also detected a decrease in maximum complex IV activity in male HbSS mice (325.5 ± 63.8 vs. 639.5 ± 51.3 pmol/(s*mg), p=0.02). Treatment with DFP improved proteinuria (2.66 ± 0.09 vs. 1.3 ± 0.14 mg/24hrs, p=0.0011) and GFR (165.3 ± 9.4 vs. 236.6 ± 12.6 μl/min, p=0.0058) in male HbSS mice. Conclusion: Iron accumulation causes renal injury which may be attributed to ferroptosis and mitochondrial dysfunction in SCD mice. Funding: NHLBI—R00HL144817 and ASN Norman Siegel Research Grant to MK. 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.
Mindfulness-based Stress Reduction and Endothelial Function in Chronic Kidney Disease
Authors: Cruz Julianna , Zanuzzi Matias , Jeong Jinhee , DaCosta Dana , Park Jeanie 
Published: May 2024

Introduction: Chronic Kidney Disease (CKD) is associated with increased cardiovascular disease risk in part due to endothelial dysfunction. Studies have suggested that mindfulness-based stress reduction (MBSR) may have beneficial physiologic effects on cardiovascular disease risk; however, the potential beneficial effects of MBSR on endothelial function in CKD are unknown. We tested the hypothesis that MBSR improves endothelial function in patients with CKD. Methods: Participants with CKD (Stages III-IV) were enrolled and randomized to 8 weeks of MBSR versus the Health Enhancement Program (HEP), a structurally parallel control intervention to MBSR. Each intervention consisted of daily homework and 2.5hr weekly classes of mindfulness meditation (for MBSR) and health education (for HEP). Each intervention also included a day-long retreat. Endothelial function was quantified as brachial artery reactive hyperemia index (RHI) using peripheral artery tonometry (EndoPAT). RHI and offce blood pressure were obtained at baseline and at the end of the intervention. Intervention groups were also stratified into subgroups based on normal (RHI ≥2.10) and abnormal (RHI <2.10) baseline values for secondary analyses. Results: Data were obtained from 37 participants with CKD who were enrolled and randomized to MBSR (N=21) versus HEP (N=16). There were no differences in baseline characteristics, hemodynamics or RHI between groups. There were no significant differences in baseline versus end of study RHI within (HEP p=0.76; MBSR p=0.57) and between intervention groups (p=0.36). There was no difference in change in RHI after MBSR between the normal and abnormal RHI subgroups. Conclusions: MBSR did not have significant effects on endothelial function measured as RHI among individuals with CKD. Supported by NIH Grants R33AT010457 and R01HL135183. 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.
Female mice with menopause exhibit coronary microvascular disease
Authors: Yang Mingya , Li Xinrui , Ramirez Francisco , Makino Ayako 
Published: May 2024

Menopause is a natural process as women age, and women with menopause are at higher risk of having cardiovascular diseases than men at the same age. Coronary microvascular disease (CMD) is one of the causes of angina, and the prevalence of CMD is higher in women than in men, and more postmenopausal women have CMD than premenopausal women. However, the causes of CMD in postmenopausal women are not clear. In this study, we investigate whether and how menopause leads to coronary microvascular disease in female mice. Menopausal mice were generated by administering a 20-day injection of 4-Vinylcyclohexene diepoxide (VCD, 160 mg/kg/day in sesame oil, i.p.). VCD gradually destroys primordial and primary follicles in ovaries and leads to ovary failure while keeping the ovary tissues intact; this model is close to the natural progression of human menopause. The vehicle, sesame oil, was administered in control mice. Coronary flow velocity reserve (CFVR) was measured to assess coronary microvascular function. Isometric tension was conducted in third-order coronary arteries (CAs). Capillary density was measured and compared in the left ventricle. Experiments were performed at 6 weeks (perimenopause period) and 8 weeks (post-menopause period) after the injection of VCD or vehicle in female mice. There was no significant difference in CFVR between VCD-injected mice and vehicle-injected mice 6 weeks after the injection. However, at 8 weeks after the injection, VCD-injected mice exhibited a significant decline in CFVR compared to the control mice. Coronary microvascular dysfunction can be driven by attenuated vascular relaxation in small coronary arteries and/or capillary rarefaction. We first conducted isometric tension and found that endothelium-dependent relaxation was significantly attenuated in VCD-injected mice at 8 weeks after the injection, but not at 6 weeks, compared to the controls. There was no significant difference in EC-independent relaxation between the two groups at any age. Interestingly, there was no significant difference in capillary density between VCD-injected mice and vehicle-injected mice at 6 weeks and 8 weeks after the injection. Postmenopausal mice, but not perimenopausal mice, develop CMD due to attenuated endothelium-dependent relaxation. This suggests that improving endothelium-dependent relaxation is the potential mechanism to treat CMD in postmenopausal women. Supported by NIH R01HL142214 and DOD W81XWH2110472. 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.
Effect of Maternal High Fat Diet on the Hypothalamus-Pituitary-Adrenal Gland (HPA) Axis of the Offspring in Sheep
Authors: Ahir Digishaben , Han Hyungchul , Jellyman Juanita 
Published: May 2024

Maternal consumption of a high fat diet (HFD) during pregnancy is associated with metabolic dysfunction and altered HPA axis function in the offspring. These effects are well established in species with short gestation length (e.g., rodents), but less established in species with longer gestation periods more comparable with humans. The objective of the study was to determine the effect of maternal HFD on basal and stimulated cortisol secretion in the offspring at 16 weeks of age in sheep. All experiments were approved by the Institutional Animal Care and Use Committee at Cal Poly Pomona. Pregnant ewes were assigned to control (n=3) and HFD (n=3) groups. The control group was fed farmers best complete ewe and ram pellets. The HFD group was fed the same diet with an additional 30% rumen protected fat (Megalac, Volac Wilmar Feed Ingredients Ltd). After birth lambs were weaned at 12 weeks of age and given free access to control pellet diet with grains. To assess adrenal cortisol secretion at 16 weeks, lambs were infused intravenously with adrenocorticotropic hormone (ACTH; 2 ug/kg cortrosyn in 1 mL saline). Blood samples (1 mL) were taken through the jugular catheter at −30, −15, and 0 min (immediately before) and 5, 15, 30, 60, 90, and 120 min after ACTH administration for measurement of plasma cortisol by ELISA. Data were analyzed by two-way repeated measures ANOVA with a Tukey posthoc test. Basal plasma cortisol tended to be higher in HFD (32±8 ng/mL) than control (13±3 ng/mL) lambs, but this did not reach statistical significance. Plasma cortisol was higher than baseline from 15 to 90 minutes after ACTH administration in all lambs (p<0.05). The increment in plasma cortisol was higher in HFD than control lambs from 15-90 minutes (p<0.05). Accordingly, the maximum increase in plasma cortisol at 60 minutes and was higher in HFD (245±8 ng/mL) than control lambs (121±50 ng/mL p<0.05). These preliminary data suggest that maternal consumption of a high fat diet during pregnancy may increase basal and stimulated activity of the HPA axis in sheep. The study was funded by a Strategic Interdisciplinary Research Grant (SIRG) at California State Polytechnic University, Pomona. 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.
Neutrophil NADPH oxidase regulation by oxidative phosphorylation and accessory glucose metabolic pathways
Authors: Jobe Tyler , Stephan Jonah , Hill Bradford , Wysoczynski Marcin 
Published: May 2024

Neutrophils produce reactive oxygen species (ROS) to extinguish pathogens and regulate intracellular signaling. The major producer of ROS in neutrophils is the NADPH oxidase, which is fueled by NADPH generated via the oxidative pentose phosphate pathway. It remains unclear how other accessory pathways of glucose metabolism and mitochondrial activity influence the oxidative burst in neutrophils. The respiratory burst in bone marrow-derived neutrophils was stimulated with phorbol 12-myristate 13-acetate (PMA) in the presence or absence of an inhibitor of glycogen breakdown (glycogen phosphorylase inhibitor; GPi), inhibitors of mitochondrial respiration (antimycin A and rotenone), or an inhibitor of serine biosynthesis (NCT503). Respiratory burst was also measured under conditions of limited glucose and glutamine. ROS production was measured via extracellular flux analysis or via dihydrorhodamine fluorescence. In both male and female mouse neutrophils, inhibition of glycogen breakdown by GPi delayed initiation of the oxidative burst in response to PMA (n = 6, p<0.05, Student’s T-test and Repeated Measure’s ANOVA). Inhibition of mitochondrial oxidative phosphorylation or inhibition of the serine biosynthetic pathway sustained ROS production in PMA-stimulated neutrophils (n = 6, p<0.05, Student’s T-test). Removal of glucose and glutamine showed a truncated oxidative burst (n = 6, p<0.05, Student’s T-test). Ultimately, these findings suggest that glycogen breakdown fuels the initial activation of the oxidative burst, while mitochondrial activity and the serine biosynthesis pathway control the magnitude and duration of neutrophil ROS production. Furthermore, utilization of exogenous glucose and glutamine are necessary for the entire oxidative burst. Future studies will continue to illustrate the mechanisms of neutrophil metabolic plasticity as well as connect their significance in the context of wound healing, exercise, and chronic inflammatory diseases. NIH: R01HL141191, NIH: P01 HL078825. 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.