bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alda‐1 shields mitochondrial dynamic proteins from hyperoxia via Aldh2 activation
Authors: Patil Sahebgowda , Fukumoto Jutaro , Saji Smita , Hernandez‐Cuervo Helena , Alleyn Matthew , Lockey Richard F , Kolliputi Narasaiah , Galam Lakshmi 
Published: June 2021

RationaleAcute respiratory distress syndrome (ARDS) is associated with fluid filled lungs and hypoxia. Thus, ARDS patients are placed on supplemental oxygen; however, hyperoxia can damage the lungs, cause mitochondrial dysfunction, and ultimately lead to acute lung injury in animal models of ARDS. Mitochondrial aldehyde dehydrogenase 2 (Aldh2) metabolizes dangerous, reactive products, such as 4‐hydroxynonenal, that otherwise causes oxidative stress. The focus of this research is to determine if Alda‐1, an Aldh2 activator enhances the activity of Aldh2, thus alleviating hyperoxia damage by preventing mitochondrial dysfunction and reducing immune cell infiltration. It also determined if administration of Alda‐1 recovers mitochondrial dynamics and reduces cytokine levels and immune cell infiltration.MethodsC57BL/6 mice were exposed to hyperoxia for 48 hours with DMSO (Control) and Alda‐1 (20 mM) via alzet pumps on the dorsal side of mice. The mice were divided into four groups: normoxia + DMSO (room air), normoxia + Alda‐1, hyperoxia + DMSO, and hyperoxia + Alda‐1. The lungs were harvested and the bronchoalveolar lavage (BAL) fluid was collected and analyzed by immunoblot and cytokine levels.ResultsImmunoblot analysis of lung lysate demonstrates that mice treated with Alda‐1, compared to mice treated with DMSO, during hyperoxia have decreased levels of OPA1 and Drp1, indicating that Alda‐1 shields against oxidative stress for proteins associated with mitochondrial dynamics. Moreover, the BAL fluid analysis reveals less infiltration of macrophages in mice treated with Alda‐1 versus mice treated with DMSO alone. These results indicate that activation of Aldh2 via Alda‐1 is protective against hyperoxia‐induced acute lung injury and may be a viable therapeutic agent for ARDS.ConclusionThese findings suggest that Alda‐1, an Aldh2 activator, maintains mitochondrial homeostasis and reduces immune cell infiltration in this mouse model of ARDS and may be a novel therapeutic agent in ARDS.Support or Funding InformationThis work is supported by NIH RO1 grant (HL105932) to N.K. and AHA grant (#17SDG32780002) to L.G.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Requirement of Sterol Regulatory Element‐Binding Protein Pathway in Pancreatic Ductal Adenocarcinoma
Authors: Myers Stephanie , McGuire Meredith , Shao Wei , Ewachiw Ted , Rasheed Zeshaan , Matsui William , Espenshade Peter 
Published: June 2021

Pancreatic ductal adenocarcinoma (PDAC) is a very aggressive tumor with limited diagnostic and therapeutic options. Due to its proliferative nature, PDAC tumor cells have a high demand for lipid synthesis. However, this tumor is known to be poorly vascularized and nestled within a hypoxic environment. As lipid synthesis is a highly oxygen‐consumptive process, neoplastic cells are challenged with meeting the demand for lipids. Cells, including cancer cells, respond to lipid conditions through sterol regulatory element‐binding proteins (SREBPs). SREBPs are master regulators of lipid homeostasis and require SREBP cleavage activating protein (SCAP) during signaling to regulate lipid synthesis. While the SREBP pathway has been implicated in several cancers, its role in PDAC has not been examined. Here, we acquired four patient‐derived pancreatic adenocarcinoma cell lines, knocked out SCAP, then followed with a rescue. We performed functional growth assays using both lipid‐poor and lipid‐rich conditions as well as subcutaneous and orthotopic xenografts in nude mice. In lipid‐poor conditions, SCAP knockout cells showed significantly reduced growth when compared to wildtype or SCAP rescued cells. In subcutaneous tumor xenografts, SCAP knockout cells exhibited reduced tumor volume in 3 out of 4 cell lines when compared to parent wildtype tumor cells. Similarly, SCAP knockout cells grew poorly in pancreatic orthotopic xenograft models. Our results demonstrate that loss of SCAP in PDAC tumor cells alters growth both in vitro and in vivo. These findings suggest SCAP may be useful as a therapeutic target in combating PDAC.Support or Funding InformationNIH T32 OD011089 (SM); Allegheny Health Network Cancer Grant (PJE); Sol Goldman Pancreatic Cancer Research Center Grant from Sidney Kimmel Comprehensive Center (PJE); NIH F31LB131185 (MM)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Targeting Glucose Metabolism in Medulloblastoma
Authors: Telang Sucheta , Meiman Evan , Burlison Joseph 
Published: June 2021

Medulloblastoma is the most common malignant brain tumor of childhood. Although current treatment approaches for this cancer have improved overall survival, they leave devastating and lifelong sequelae and the mortality remains high. Novel targeted therapies are therefore crucial to improve survival in these children and decrease treatment‐related toxicity.Medulloblastoma development is largely driven by deregulation of normal cerebellar proliferation wherein the sonic hedgehog (Shh) pathway plays a critical role. Activating mutations of Shh genes are frequent in medulloblastoma and promote their rapid growth. In addition, highly aggressive Shh‐active medulloblastomas also exhibit mutations of the Ras/MAPK pathway and increased HIF‐1α, which are observed to stimulate glycolysis by activating the 6‐phosphofructo‐2‐kinase/fructose‐2,6 bisphosphatase family of enzymes (PFKFB1‐4). The PFKFBs produce fructose‐2,6‐bisphosphate (F26BP), a potent activator of 6‐phosphofructo‐1‐kinase, a rate‐limiting step in glycolysis. Recent data indicate that the PFKFB4 family member is increased in multiple human tumors and cancer lines, required for cell survival in aggressive brain tumors and strongly induced by hypoxia. We have found that the PFKFB4 enzyme was highly expressed in a series of patient‐derived medulloblastomas and correlated significantly with expression of the Shh pathway effector Smoothened (SMO) and GLI1. Through HIF‐1α upregulation, hypoxia was observed to strongly induce PFKFB4 expression in Shh‐active medulloblastoma cells and silencing PFKFB4 in these cells markedly suppressed F26BP and glycolytic flux to lactate and significantly decreased cell survival and proliferation, more prominently in hypoxia, indicating that PFKFB4 may be preferentially required for survival and growth under hypoxia. In addition, we found that co‐silencing PFKFB4 with SMO or GLI1 markedly decreased cell survival. We have recently developed a novel selective small molecule inhibitor of PFKFB4 and examined the effects of inhibiting PFKFB4 and the Shh pathway simultaneously. We found that simultaneous administration of the PFKFB4 inhibitor and inhibitors of the Shh pathway synergistically decreased Shh‐active medulloblastoma cell viability. Taken together, our data indicate that targeting PFKFB4 may be a valid therapeutic option against medulloblastoma and strongly support the further examination of simultaneous inhibition of PFKFB4 and the Shh pathway as a treatment strategy in medulloblastoma.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Sustained Polyamine Depletion for the Treatment of Pancreatic Ductal Adenocarcinoma
Authors: Dobrovolskaite Aiste , Altomare Deborah , Phanstiel Otto 
Published: June 2021

Of all human tissues, the human pancreas has the highest level of the polyamine spermidine. Pancreatic cancers use these high levels to drive their growth. Indeed, polyamine metabolism plays critical roles in many cellular processes including transcription, translation, and chromatin remodeling. Therefore, therapies, which deplete the intracellular pools of the native polyamines putrescine, spermidine, and spermine, result in cell growth arrest. Inhibitors have been designed to inhibit the rate limiting enzyme in polyamine biosynthesis, i.e., ornithine decarboxylase (ODC). Indeed, the ODC inhibitor difluoromethylornithine (DFMO), has a forty year history in the clinic with mixed results as an oncology therapeutic. Unfortunately, DFMO‐treated cancer cells often respond by increasing polyamine import to restore their depleted polyamine pools. Therefore, in order to establish sustained intracellular polyamine depletion, a combination therapy of DFMO and a polyamine transport inhibitor (PTI) is required.New polyamine transport inhibitors are needed because all existing PTIs are polyamine‐based and can give rise to off‐target effects. To address this need, we have developed new PTI agents predicated upon a benzoic acid scaffold. This report describes our development of these new agents and their use to inhibit the uptake of radiolabeled spermidine and block the rescue of DFMO‐treated pancreatic cancer cells by exogenous spermidine. Since pancreatic ductal adenocarcinoma (PDAC) is the most common pancreatic cancer, we have focused on this cancer type in our studies. A success here could lead to new therapies for the world's most deadly cancer, which currently has a five year survival of only 8%.Support or Funding Information2016 Florida Translational Research Program and the 2018 Bankhead‐Coley Cancer Research Program Award # 8BC05.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Modulation of lipid accumulation in monocytes and macrophages by cyclodextrin‐based nanocarriers for alpha‐tocopheryl phosphate
Authors: Zingg Jean‐Marc , Stamatiou Christina , Daunert Sylvia 
Published: June 2021

Vitamin E can modulate the CD36/FAT scavenger receptor/fatty acids transporter activity and affect lipid accumulation in monocytes and macrophages, important events for inflammation, lipotoxicity and foam cells formation during atherosclerosis. Similar to that, cyclodextrins (CD) can sequester and trigger export of lipids and influence cholesterol‐mediated signaling and gene expression leading to macrophages reprogramming and lipid lowering effects in a number of disease models. We have now combined the phosphorylated vitamin E analogue (alpha‐tocopheryl phosphate, αTP) and beta‐cyclodextrin (βCD) in a novel formulation to evaluate its regulatory effects and mechanisms of action on lipid accumulation in human monocytes/macrophages. In human THP‐1 monocytes and macrophages, the αTP/βCD complex not only increased the cellular delivery of αTP, but also reduced lipid accumulation by reducing CD36/FAT surface exposition and/or by enhancing the removal of cholesterol from the cells/membranes. A comparable activity was observed with higher order complexes of αTP/βCD with three types of modified starches or chitosan that may be useful as protective vehicle to increase oral, dermal or ocular delivery, or act as deposit‐enhancer in mucosa for delivery across epithelia. Moreover, preliminary results suggest that the αTP/βCD complex can influence signal transduction and gene expression pathways centrally involved in regulating cellular lipid homeostasis and inflammation. Thus, by acting as a Dual Action Lipid‐lowering Complex (DALC), αTP/βCD may not only increase the delivery of αTP and reduce cellular lipid accumulation by influencing CD36‐mediated signaling and gene expression relevant for lipid homeostasis, inflammation and cellular senescence, but also by stimulating βCD‐mediated lipid removal and macrophage reprogramming. In vivo, similar or better reductions of cellular lipids/cholesterol may be achieved possibly at lower concentrations as result of increased bioavailability and stability of αTP and of enhanced βCD‐mediated lipid exchange and macrophages reprogramming relevant not only for inflammation and atherosclerosis, but also for non‐alcoholic steatohepatitis (NASH), tumorigenesis and Parkinson's Disease.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Evaluation of n‐3 fatty acid status of pregnant women in Zambia with relation to HIV infection
Authors: Majid Sonoor , Kisling Sophia , Allen James , Wood Charles , Chunda Catherine , DiRusso Concetta 
Published: June 2021

Malnutrition and human immunodeficiency virus (HIV) are independent risk factors for impairment of fetal and early childhood development, altered brain structure, and reduced cognitive function. Docosahexaenoic acid (DHA (C22:6cisΔ 4,7,10,13,16,19 ω3)) is a fatty acid that is abundant in the brain, retina, and cerebral cortex. Additionally, DHA‐derived eicosanoids function in the resolution of inflammation. Thus, there it is hypothesized to be a link between DHA status, brain function and inflammation that may be critical in HIV positive pregnant women. Brain development and DHA incorporation into neuronal tissues occur largely during the last trimester of pregnancy to 24 months after birth. DHA may be acquired either through de novo synthesis from linolenic acid (LN (C18:3 cisΔ 9,12,15 ω3)) or from the diet. The present study was undertaken to evaluate DHA status in terms of dietary intake and plasma levels in pregnant women in Zambia, a country where food insecurity and HIV infection are highly prevalent. Initially, 113 women were enrolled in this study at the antenatal clinic of the Women and Children's Hospital in Lusaka, Zambia. The participants completed a health and dietary questionnaire and then a fasting blood sample was acquired. Ultimately, 45 HIV seronegative and 46 HIV seropositive women were included in the study cohort. Pre‐pregnancy BMI had a mean of 22 and ranged from 17.9 to 24.9, thus none of the women were clinically underweight. Gestational age ranged from 20–29 weeks with an average of 22. Blood lipids were measured to quantitate and compare triglyceride, lipoprotein and total cholesterol, and fatty acid levels. Total fatty acid profiles were assessed using gas chromatography/mass spectrometry (GC/MS). Essentially all participants reported eating fish on a regular basis averaging 2‐times per week and most (80%) consumed the small sardine‐like fresh water fish Kapenta, that is known to be relatively high in DHA. However, plasma fatty acid profiles indicated a high ω6 to ω3 ratio and low LN, EPA and DHA levels overall. There were no significant differences in these values between HIV seropositive and seronegative participants. Therefore, we propose DHA supplementation is warranted to raise blood DHA levels during pregnancy in Zambia to address both child development and the mother's health.Support or Funding InformationWorld Health Organization (WHO)Undergraduate Creative Activities and Research Experience (UCARE)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of Nicotine on Adipocyte Production of Resistin and NF‐Kβ Translocation
Authors: Peter Jennica Renae 
Published: June 2021

The relationship between nicotine and inflammation is complex and understanding the role of nicotine in inflammation could hold the key to treating many inflammatory diseases. Resistin is a pro‐inflammatory adipokine that is associated with inflammatory diseases, including ulcerative colitis. Anecdotal evidence indicates that patients with ulcerative colitis can achieve symptom relief by smoking commercial cigarettes, and this has prompted human and murine studies. We hypothesized that the mechanism through which nicotine affects adipocytes is a decrease in resistin expression via modification of NFKb activation. 3T3‐L1 mouse fibroblasts were differentiated into adipocytes and exposed to 10uM nicotine for 26 hours. We found that resistin release was decreased in nicotine‐treated adipocytes (n=23, μ=57.193 pg/ml, s=29.546) when compared to the control (n=8, μ=4,933 pg/ml, s=8.068), nearly a 100‐fold decrease. We conclude that nicotine reduces the secretion of resistin from adipocytes and that this may be the immunosuppressive mechanism underlying nicotine effects in the treatment of chronic inflammatory disease.Support or Funding InformationFort Lewis College BiologyThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
H‐Ras Signaling Mediates Microglia Proliferation Contributing to Neuropathology in INCL Mice
Authors: Sadhukhan Tamal , Bagh Maria , Appu Abhilash , Mondal Avisek , Kong Eryan , Liang Yinming , Zhang Zhongjian , Mukherjee Anil B 
Published: June 2021

In virtually all neurodegenerative diseases, including infantile neuronal ceroid lipofuscinosis (INCL), neuronal death follows microglial proliferation. Proliferating microglia release toxic cytokines, which are suggested to cause neuroinflammation and progressive death of viable neurons contributing to neurodegeneration. Despite this knowledge, the molecular mechanism(s) underlying microglial proliferation in neurodegenerative diseases remains poorly understood. INCL is a neurodegenerative lysosomal storage disease, caused by inactivating mutations in the CLN1 gene encoding palmitoyl‐protein thioesterase‐1 (PPT1). PPT1 depalmitoylates S‐acylated proteins (constitutes of ceroid), essential for their degradation by lysosomal hydrolases. Thus, PPT1‐deficiency causes lysosomal ceroid accumulation leading to INCL. S‐palmitoylation (also called S‐acylation) is a reversible post‐translational lipid‐modification, which regulates the function of many proteins, especially in the brain. In humans, a family of 23 palmitoyl‐acyltransferases (PATs), containing a DHHC (Asp‐His‐His‐Cys) motif (DHHC‐PATs), catalyze S‐palmitoylation. In contract, thioesterases, localized to the cytosol or to the lysosome, depalmitoylate S‐acylated proteins. We previously reported that cytosolic thioesterase, APT1, requires S‐palmitoylation for membrane‐anchorage and catalyzes its own depalmitoylation to promote dynamic palmitoylation (palmitoylation‐depalmitoylation), essential for its cytosol‐membrane shuttling. Notably, proto‐oncogene H‐Ras product also requires dynamic S‐palmitoylation for cytosol‐membrane shuttling for signaling. Moreover, S‐palmitoylated H‐Ras is a substrate of APT1. Despite the demonstration that APT1 self‐catalyzes depalmitoylation, the DHHC‐PAT(s) that S‐palmitoylates APT1, remains unknown. Here we report that DHHC5 and DHHC23 catalyze S‐palmitoylation of APT1 promoting its membrane‐anchorage. Moreover, in Cln1−/− mice, which mimic INCL, the levels of S‐palmitoylated H‐Ras in the brain are significantly higher compared with those in WT controls. Unexpectedly, we found that the levels of DHHC5 and DHHC23 in Cln1−/− mice are significantly reduced. These results may suggest Ppt1‐Apt1 cross‐talk is mediated via regulation of these two DHHCs. We propose that crosstalk between Apt1 and Ppt1 elevates membrane‐anchored, S‐palmitoylated‐H‐Ras, which transduces signals to stimulate astroglia proliferation contributing to rapid progression of neurodegeneration in Cln1−/− mice.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The role of cholesterol trafficking in BACE‐1 and APP co‐localization
Authors: Levitt Claire Hoa , Tarren Anna , Cluett Edward 
Published: June 2021

Beta amyloid (Aβ) peptides play a central role in the pathogenesis of Alzheimer's disease (AD). Aβ peptides are derived from the processing of amyloid precursor protein (APP). This protein undergoes extensive processing involving two different pathways that produces several fragments. The α‐secretase pathway produces normal peptides. The pathogenic form of Aβ is derived from a cleavage product generated by beta‐site APP Cleaving Enzyme 1 (BACE‐1) that is then cleaved by γ‐secretase. Although the interaction of APP and BACE‐1 is critical for understanding how AD occurs, it is not clear how or where this occurs. Cholesterol has been identified as a risk factor in AD, and in vitro studies suggest that increased cholesterol levels promote misprocessing of APP. Our lab found that phospholipase A2 inhibitors, which inhibit the formation of membrane tubules, caused the accumulation of cholesterol in the recycling endosome in HeLa cells grown in moderate levels of LDL. APP also co‐localized to this compartment, and immunoblotting showed that the processing of APP and the association of APP fragments with cholesterol‐rich domains was altered by treatment with ONO‐RS‐082, a PLA2 inhibitor. However, BACE‐1 did not co‐localize with APP under these conditions. Surprisingly, in SY‐SH5Y cells co‐localization with BACE‐1 and APP did occur when cells were grown in low levels of LDL, which promote the synthesis of cholesterol. Using immunofluorescence/confocal microscopy and immunoblotting, we are confirming these results and extending this research by investigating the effects of statins or increased LDL on the localization and processing of these proteins.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
ABC Transporter: Atm1 and the Transport of Heavy Metals
Authors: Ureta Lyle , Hicks Dennis , Yang Janet 
Published: June 2021

ATP binding cassette (ABC) active transporters rely on the ability to bind and hydrolyze ATP with the purpose of exporting and importing molecules into and out of cells. In this study, we focus on Atm1, an ABC transporter originally discovered in yeast mitochondria. Atm1 plays a critical role in iron sulfur cluster synthesis, although the exact mechanism is not known. The protein utilized in this research is NaAtm1, from Novosphingobium aromaticivorans, which has been shown to confer heavy metal resistance when overexpressed in E. coli. The overall goal of this research is to confirm that the Atm1 that we are working with does indeed transport heavy metals, and to understand how Atm1 mediates this transport. Toward this end, four mutants of the Atm1 protein were created to dissect the mechanism of transport. The first mutant was made in the Walker B motif and is expected to be ATP hydrolysis deficient. This mutant was created by knocking out the catalysis ability of the protein by replacing a glutamate with a glutamine (E523Q). The second mutant, S526C, will be fluorescently tagged to observe changes in conformation when the protein is bound to nucleotides and/or substrate. The third mutant, K142Q, is designed to uncouple ATP hydrolysis and transport. The last mutant, K400A, is expected to eliminate the ability to bind ATP by changing a lysine to an alanine in the Walker A motif. This collection of mutations will allow us to begin our dissection of the NaAtm1 mechanism.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.