bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interleukin-1 beta Increases Glycolysis Through AKT and HIF-1 alpha in Colorectal Cancer Cells
Authors: Kim Ji Yeon , Park Bohye , Riffey Olivia , Donohoe Dallas 
Published: May 2023

Increased glucose utilization and glycolysis is an important component in colorectal cancer. Inflammation is a known promoter of cancer development and progression. It has been reported that increased production of pro-inflammatory cytokines such as interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNFα) promote glycolysis. Previously, in colorectal cancer cells, we have demonstrated that IL-1β increased glycolysis, while suppressing oxidative metabolism. However, the mechanism underlying how this pro-inflammatory cytokine increased glycolysis was unclear. We hypothesized that IL-1β promoted glycolysis by increasing AKT activation given the metabolic role of this protein in metabolism. AKT is downstream of the interleukin-1 receptor, which is the major receptor IL-1β signals through to elicit a cellular response. Here, we show that upregulation of glycolysis by IL-1β is mediated through the AKT and more specifically the downstream transcription factor hypoxia inducible factor-1 alpha (HIF-1α). Knockout of HIF-1α completely abolished the elevated glycolysis induced by IL-1β. In addition, IL-1β had profound effects on mitochondrial function through reducing basal respiration, spare respiratory capacity, and maximal respiration. These data suggest a mechanism by which IL-1β through AKT activation and HIF-1α, regulates glycolysis in colorectal cancer cells. This work was supported by USDA NIFA (2019-67017-29261). This is the full abstract presented at the American Physiology Summit 2023 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.
Alteration in S6K1-IRS1 signaling is uncoupled from whole body insulin sensitivity in animals treated with leucine or ketoisocaproic acid
Authors: Mann Gagandeep 
Published: May 2023

Introduction: Plasma levels of branched-chain amino acids and their metabolites, branched-chain ketoacids are increased in insulin resistance, a condition that can lead to type 2 diabetes mellitus. Questions remain as to whether elevated levels of these metabolites cause, or are a consequence of insulin resistance. We previously showed that leucine and its metabolite ketoisocaproic acid (KIC) suppressed insulin-stimulated glucose uptake in L6 myotubess. Leucine and KICwith an increase in e S6K1 activation and phosphorylation of an inhibitory serine IRS-1 residue. The objective of this study was to analyze the effect of KIC gavage on skeletal muscle and liver insulin signaling and how this impacts whole-body insulin sensitivity. We hypothesized that KIC gavage will reduce whole-body insulin sensitivity and in response to the activation of the S6K1-IRS-1 pathway as shown in vitro. alter skeletal muscle and liver insulin signaling. Methods: Five-week-old male Sprague-Ddawley rats were starved for 24 hours. Rats were then gavaged with 0.75ml/100g of water, leucine (22.3g/L) or KIC (30g/L) twice, ten minutes apart, and then either sacrificed at different timepoints post-gavage (0.5-3h). A different set of rats were starved for 6 hours and then or injected with insulin an hour after the first gavageleucine or KIC gavage. Basal blood glucose levels and post insulin injection (10-120min after injection) blood glucose levels were measured., where blood glucose was measured pre (basal) and post (10-120min) insulin injection. Results: Leucine or KIC gavage had no effect on whole-body insulin sensitivity. This was consistent with no effect on ph-Akt (S473) phosphorylation. However, IRS-1 (S612, p<0.0001), S6K1 (Thr389, p<0.001) and S6 (S235/6, p<0.0001) phosphorylation were increased 30 minutes after leucine gavage in skeletal muscle and liver, but this was alleviated by the 60-minute mark. KIC gavage had no effect on the activation of these proteins. Conclusion: Despite increased S6K1 threonine phosphorylation and IRS-1 serine phosphorylation in skeletal muscle and liver in response to leucine gavage, there was no effect on whole-body insulin sensitivity. Unlike in studies with myotubes, KIC did not activate S6K1-IRS-1 signaling. Thus, although insulin resistant states exhibit increased plasma leucine and KIC levels, their supplementation does not reduce insulin sensitivity, suggesting that their increased levels are a consequence of insulin resistance and not causative. s. This suggests other mechanisms and/or tissues may play a role in regulating whole-body insulin sensitivity during leucine/KIC gavage. NSerc, York University This is the full abstract presented at the American Physiology Summit 2023 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.
Drosophila Clc-c as a model of human CLC-5 and Dent Disease type 1
Authors: Reynolds Carmen , Gillen Christopher , Dow Julian , Romero Michael 
Published: May 2023

Introduction: Dent Disease type 1 (DD1) results from X-linked, mutations in CLC-5 (2Cl-/H+ exchanger) and results in progressive renal failure by 20-40. DD1 is characterized by kidney Ca2+ mishandling, and subsequent hypercalcuria, calcium oxalate (CaOx) kidney stones, and kidney calcification as well as proteinuria. We identified Drosophila Clc-c as the CLC-5 homolog with conserved amino acids at DD1 mutation sites. We hypothesize that Clc-c shares functional similarities in Cl- transport, Ca2+ homeostasis and protein processing. Methods and Results: By voltage clamping Xenopus oocytes expressing Clc‑c and CLC-5, we find that both are electrogenic and have the same outward-rectifying current in Cl- solutions. Cl- transport (current at +80mV) was lowered by acidity (2.37±0.55 μA, pH 6.0, P=0.06), but not by alkaline solution (4.45±0.96 μA, pH 8.5, P= 0.7) when compared to the standard solution of pH 7.5 (4.97±1.12 μA). Similarly, Cl- transport was lowered by homologous DD1 mutations S393L (0.67±0.098 μA, P<0.0001), R494W (2.9±0.46 μA, P =0.006), and Q777x (1.13±0.28 μA, P =0.0001) vs. WT (7.4±1.2 μA) as observed previously for CLC-5 DD1 mutations: S244L, R345W, and Q629x (Tang et al, Physiol Rep 4[8], 2016). To determine cell membrane and possible intracellular localization of DD1 mutations, HA-tagged Clcc and mutations (identical placement as in CLC-5-HA, Tang 2016) were made. Likewise, transgenic Drosophila expressing Clc-c-GFP were made to localize Clc-c in cell and intracellular membranes of renal tubules (Malpighian tubules, MT) in vivo (Judd-Mole, U Monash, Dissertation, 2016). RNAi MT knockdowns of Clc-c (Clc-c-KD) were made and resulted in 50% decrease in Clc-c mRNA expression. CaOx crystals in anterior MT (7 days after eclosure) were present in all Clc-c-KD and were more abundant (15±4 crystals/fly) than w1118 controls (5±2 crystals/fly, P= 0.02). MT secretions showed that Clc-c KD flies contained higher [Ca2+] while all other cations (Na+, NH4+, K+, Mg2+), and volume were the same as w1118 . Similarly, urinary protein concentration (4-6 pooled flies per n) appears elevated in DD1 flies (1.41 ± 0.14 mg/mL, n=3) vs w1118 (1.16 ± 0.08 mg/mL, n=5). Conclusion: Drosophila Clc-c has similarities to human CLC-5 including impaired function of voltage-gated Cl- transport, homologous DD1 mutations, increased CaOx crystal formation, and elevated urinary [Ca2+] and protein. Our results indicate that the Drosophila Clc-c avatar may help to provide more direct insights to the cellular and organismal pathophysiology for future investigations of Cl- transport, Ca2+ homeostasis and urinary protein loss in DD1. F32 DK128987, T32 DK007013 This is the full abstract presented at the American Physiology Summit 2023 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.
Sarcolipin ablation decreases whole body VO2 in young female nice
Authors: Brahmbhatt Aditya , Chambers Paige , Hashemi Ashkan , Tupling Arthur 
Published: May 2023

The sarco(endo)plasmic reticulum calcium (Ca2+) ATPase (SERCA) pump is a major regulator of cytosolic Ca2+ in striated muscle. Sarcolipin (SLN) reduces SERCA-mediated Ca2+ pumping efficiency and is a key regulator of muscle metabolism and contractile function. With SERCA activity comprising approximately 12% of whole-body metabolic rate, the inefficient SERCA Ca2+ cycling promoted by SLN would be predicted to increase metabolic rate. Although SLN is involved in adaptive diet-induced thermogenesis and overexpression of SLN increases metabolic rate and protects against diet-induced obesity, we found previously that SLN ablation had no effect on whole body metabolic rate or body composition in male mice that were fed a standard chow diet. However, unpublished work from our lab indicates that SLN expression in mouse soleus is significantly higher in females compared with males. Therefore, the purpose of this study was to investigate the effects of SLN ablation on body composition and metabolic rate of female mice. Adult (4-6mo) female wild type (WT) and SLN knockout (KO) mice (n=4 per group) were used to collect anthropometric measures (adiposity and body weight) and were housed in a comprehensive lab animal monitoring system (CLAMS) over a 48-hour period to assess daily whole body VO2 and total cage activity. With SLN ablation, total whole body VO2 (ml/kg/hr) was lower (p<0.05) in the KO females (3534 ± 95.1) compared to WT females (5080 ± 98.8), with no differences (p>0.05) found for total cage activity (counts) (WT, 14935.42 ± 1799.6 vs. KO, 11860.83 ± 679.48), body weight (grams) (WT, 20.97 ± 0.76 vs. KO, 22.18 ± 0.80), or adiposity (arbitrary units) (WT, 5.18 ± 1.71 vs. KO, 2.12 ± 0.36). These results showing that high levels of endogenous muscle SLN expression in female mice influence whole-body metabolism even under chow-fed conditions, demonstrate a potential important sex difference in whole body physiology and metabolism. Natural Sciences and Engineering Research Council of Canada (NSERC) [grant number 311922-05 (to A.R.T.)] This is the full abstract presented at the American Physiology Summit 2023 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.
Exercise-induced upregulation of APOE expression is attenuated by dietary supplementation with resveratrol
Authors: Allard Joanne , Graham-Hyatt Shantol , Mulgrave Verona , Alsayegh Abdulrahman 
Published: May 2023

The ε4 variant of the Apolipoprotein E gene (APOE4) is the most prevalent genetic risk factor for Alzheimer’s disease (AD). Approximately 25% of people carry at least one copy of the variant which increases risk of AD two-to-three-fold relative to those who carry the ε3 variant. Low ApoE levels are typically reported in Alzheimer’s patients and animal studies have reveal lower levels of ApoE in ε4 carriers relative to ε3 carriers. Therefore, reduced ApoE levels has been associated with increased risk for dementia. Physical exercise and active lifestyles are well-accepted therapeutic strategies for the prevention or delay of Alzheimer’s disease and other dementias, Additionally, there is growing evidence that the consumption of antioxidant nutritional supplements may also be therapeutic and slow progression of AD. But the effect of physical activity or antioxidant intake on APOE expression is not well-studied.The objective of this study is to determine the impact of exercise and resveratrol intake on APOE expression. We hypothesized that both resveratrol intake and exercise would increase APOE expression in brain with an additive effect when combined. Targeted replacement mice, homozygous for either APOE3 or APOE4 were randomized into four groups based on activity and resveratrol dietary supplementation: sedentary standard, sedentary resveratrol, exercise standard, and exercise resveratrol. Exercised groups were subjected to daily treadmill running for 8 weeks. Resveratrol treated groups were fed a chow supplemented with resveratrol. Results showed that exercise induced a significant increase in ApoE protein in brain cortex of both APOE3 and APOE4 mice. Resveratrol treatment alone had no significant effect on brain APOE expression, but in combination with exercise, attenuated the exercise-induced increase. While biochemical variations between APOE3 and APOE4 mice likely contribute to the differential risk for AD, the exercise-induced increase in ApoE levels in both genotypes supports a role for APOE in the therapeutic mechanisms of exercise. The timing of antioxidant supplementation in conjunction with exercise interventions should be critically considered to ensure best therapeutic efficacy of exercise. This research was supported by NIH grants R25AG047843 and 2U54MD007597-31 This is the full abstract presented at the American Physiology Summit 2023 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.
Role of preeclampsia on insulin-induced vasorelaxation
Authors: Rodríguez Reyes Betzabel , Bobadilla Rosa , Tufiño Martínez Cecilia , Madrigal Aguilar Damian , Mungia Venegas Julio 
Published: May 2023

The objective of this project was to evaluate whether PE alters the vascular response to insulin. The physiological insulin resistance characteristic of pregnancy is increased in preeclamptic (PE) conditions. With the hypothesis that PE diminishes insulin vascular effects we used a conventional isolated aorta rings preparation to study insulin-induced relaxation on phenylephrin (Phe) pre-contracted vessels and Phe induced contraction in the presence or absence of insulin. Vessels were obtained from non-pregnant rats (NP) with subrenal aortic coarctation (SRAC), pregnant (P) and pregnant rats with SRAC (PE). Experiments were performed in thoracic or abdominal aorta rings with or without endothelium. The results show that PE increases the contractile response to Phe in the thoracic and abdominal aorta compared to P (PE vs P p<0.01). Incubation with insulin did not modify the thoracic or abdominal aorta Phe induced contraction of any of the three groups with and without endothelium.On the other hand, insulin induced relaxation was more evident in vessels with endothelium and was decreased both in the thoracic and the abdominal aorta of PE group (PE vs P p<0.01; PE vs NP-CARS p<0.01).In conclusion, PE decreases endothelium-dependent insulin-induced relaxation suggesting PE deteriorates insulin-PI3K-NO pathway. Funding: Consejo Nacional de Ciencia y Tecnología(CONACyT) This is the full abstract presented at the American Physiology Summit 2023 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.
Centrally derived gasotransmitter modulation of hypoglossal motoneuron activity
Authors: Browe Brigitte , Prabhakar Nanduri , Garcia Alfredo 
Published: May 2023

Airway obstruction during inspiration is a hallmark trait of sleep apnea (SA). In mice, genetic elimination of the CO producing enzyme, heme oxygenase-2 (HO-2), leads to a SA phenotype predominately associated with recurrent airway obstruction. This phenotype is mitigated by either inhibition or genetic ablation of the H2S producing enzyme, cystathionine g-lysase (CSE). While these observations indicate that mutual interactions between HO-2/CO and CSE/H2S are important for regulating airway clearance, the extent of contribution from these interaction in the central nervous system to airway tone are unclear. Here, we determine how HO-2/CO and CSE/H2S impact inspiratory output from the hypoglossal nucleus (XIIn) in the isolated rhythmic brainstem slice preparation. We hypothesize that these enzymes and their respective gasotransmitter products locally interact in the inspiratory circuit to modulate the input-output (I/O) relationship between preBötC and XIIn. Electrophysiological studies conducted in brainstem slices from mice (P5-12) showed that HO-2 dysregulation, using either in wildtype slices exposed to Cr (III) Mesoporphyrin IX chloride or in slices from HO-2 null mice, increased transmission failure from preBötC to XIIn and altered the I/O relationship between the rhythm generating network and XIIn. HO-2 dysregulation also increased subnetwork activity in the preBötC that was associated with a decrease in amplitude regularity. While many transmission failures to the XIIn were associated with preBötC subnetwork activity, simultaneous recordings from the preBötC, premotor area, and the XIIn revealed that preBötC subnetwork activity was reliably transmitted to the premotor field but not to the XIIn. Dual extracellular and intracellular recordings from the preBötC and individual XIIn neurons under disinhibited conditions revealed that HO-2 dysregulation reduced inspiratory drive currents received by XIIn neurons, decreased the intrinsic excitability of XIIn neurons while also reducing the amount of preBötC subnetwork activity. Additionally, targeted inhibition of CSE/H2S activity using L-PAG or by genetic elimination of CSE in HO-2 null mice mitigated these effects of HO-2 dysregulation. Thus, the mutual interactions HO-2/CSE and CSE/H2S in the medullary brainstem appear to modulate XIIn output by: (1) causing a E/I imbalance that promotes preBötC subnetwork activity; (2) suppressing inspiratory drive received in XIIn; and (3) suppressing intrinsic excitability of XIIn neurons. These findings may be key to understanding the action by which central gasotransmitters actions contribute to upper airway muscle regulation. This work was supported by NIH: P01-HL-44454; R01NS107421. This is the full abstract presented at the American Physiology Summit 2023 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.
Gastric Bypass reprograms hepatic clock machinery and improves glucose flux independent of weight
Authors: Mokadem Mohamad , Ye Yuanchao , Abu El Haija Marwa , Herz Hussein , Linden Benjamin , Chu Yi 
Published: May 2023

Background: The molecular clock machinery regulates several homeostatic rhythms, including but not limited to glucose homeostasis. We previously demonstrated that Roux-en Y Gastric Bypass (RYGB) has a weight-independent effect on glucose metabolism, and transiently reduces food intake. In this study we investigate the effects of RYGB on diurnal eating behavior as well as its effects on the molecular clock, and its requirement for the metabolic effects of this bariatric procedure in obese mice. Results: We find that RYGB reverses the high fat diet-induced disruption in diurnal eating pattern during the early post-surgery phase of food reduction (Figure1). “Dark-cycle” pair-feeding experiments improved glucose tolerance to the level of bypass-operated animals during the physiologic “fasting” phase (Zeitgeber ZT2), but not the “feeding” phase (ZT14)(Figure 2). Using a clock gene reporter mouse model ( mPer2 luciferase), we reveal that RYGB induces a liver-specific phase shift in peripheral clock oscillation with no changes to the central clock activity within the suprachiasmatic nucleus (SCN) (Figure 3). In addition, we show that weight loss effects are attenuated in obese ClockΔ19 mutant mice post-RYGB (Figure 4) that also fails to improve glucose metabolism after surgery (Figure 5), specifically early hepatic glucose production (Figure 6). Conclusion: RYGB reprograms the peripheral clock within the liver early after surgery to alter diurnal eating behavior and regulate hepatic glucose flux. US Veterans Merit Award (#I01 BX004774) This is the full abstract presented at the American Physiology Summit 2023 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.
Time dependent activation of molecular signatures is associated with Trimethylamine N oxide induced endothelial dysfunction in human microvascular endothelial cells
Authors: Shanmugham Meyammai 
Published: May 2023

Cardiovascular diseases (CVD) are the principal cause of death worldwide. Endothelial dysfunction is recognized as a crucial initiating contributing factor for CVD. Trimethylamine–N–oxide (TMAO), a gut microbiome-derived metabolite is involved in CVD progression. However, the underlying time-dependent molecular mechanisms resulting in the pathogenesis of TMAO in endothelial cells remain unclear. To investigate the time-dependent molecular signatures of TMAO-induced endothelial dysfunction in human microvascular endothelial cells (HMEC–1), we performed transcriptomics and metabolomics analysis on TMAO (50 μM) treated cells for 24H or 48H. Differentially expressed genes were used for overrepresentation analysis of pathways to determine the various molecular signatures involved. These were validated with quantitative real–time PCR, cell viability (prestoblue), and reactive oxygen species generation (DCFDA). TMAO treatment for 24H and 48H induced endothelial dysfunction, demonstrated by lowered cell viability, and elevated oxidative stress. Interestingly, time–dependent modifications in the molecular signatures were unique between time points. Indicatively, there were fewer GO biological processes and KEGG pathways suppressed, after 24H TMAO treatment. They were involved in cellular response and developmental processes. Compared to 48H treatment, a greater number of molecular signatures were activated and suppressed for GO biological processes and KEGG pathways. Upregulated DEG was enriched in pathways like oxidative stress and the production of inflammatory phenotypes, while suppressed pathways were associated with the structural organization of the ECM, endothelial cell proliferation, and collagen metabolism. This study indicates that TMAO–induced endothelial dysfunction is regulated through the mitigation of molecular gene signatures involved in oxidative stress and inflammation, activating endothelial cell remodelling. Funding source: SUTD Start-up Research Grant, and SUTD Kickstarter Initiative, Singapore This is the full abstract presented at the American Physiology Summit 2023 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.