bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serotonin 5‐HT2 receptor activation prevents the development of allergic asthma: Physiology and functional selectivity (LB575)
Authors: Nichols Charles , Nau Felix , Saravia Jordy , Alhert Terry , Cormier Stephania 
Published: June 2021

Activation of serotonin 5‐HT2A receptors has potent anti‐inflammatory effects in multiple tissues including the nd vasculature and gut. Much of these effects in whole body are through blockade of TNF‐α mediated inflammation. We have found that activation of serotonin 5‐HT2 receptors in the lung with the agonist (R)‐DOI completely blocks the development of allergic asthma in the mouse ovalbumin model. At doses of 0.01 mg/kg inhaled, airways hyperresponsiveness, lung inflammation, mucus overproduction, and eosinophilia are blocked. The molecular and cellular mechanisms underlying these effects are currently under investigation. Structure/activity studies indicate that only phenethylamine 5‐HT2 receptor agonists closely related in structure to (R)‐DOI (e.g. R‐DOM and R‐DOB) are effective in preventing the development of asthma in our model. Phenethylamine agonists more dissimilar in structure are less effective, and indoleamine agonists like lysergic acid diethylamide are ineffective. Our results indicate that phenethylamines similar to (R)‐DOI potentially represent a novel small molecule therapeutic class for the treatment of asthma as well other inflammatory diseases.Grant Funding Source: Supported by NIHR21HL095961, the American Asthma Foundation, and the Heffter Research Institute
Bio‐distribution of superparagmetic iron oxide nanoparticles (SPION’s) in the pig (LB578)
Authors: Shortt Christine , Edge Deirdre , Teughels Stephanie , Roskin Eric , Verbiest Joeri , Gobbo Oliviero , Prina‐Mello Adriele , Volkov Yuri , Markos Farouk 
Published: June 2021

Manufactured nanomaterials have been shown to be beneficial in an array of applications, including diagnosis and targeted abolition of tumour cells. The biocompatibility and bio‐distribution of these particles is immensely important for targeted drug delivery and imaging. Therefore the aim of this study was to investigate qualitative bio‐distribution of SPION’s in the pig.Female landrace pigs (20‐25 kg; n=16) were sedated i.m. with ketamine (14 mg/kg) and xylazine (2.7 mg/kg) and maintained on a continuous infusion of sodium pentobarbital (induction 30 mg/kg; maintenance 6 mg/kg/h i.v.). Dimercaptosuccinic acid (DMSA) coated nanoparticles (0.5, or 2 mg/kg respectively) were injected i.v. Blood samples were collected for a 5 hour period and stored for determination of iron using the particle electron paramagnetic resonance (pEPR) technique. Organs were harvested post mortem for MRI (1.5T) and histological evaluation.OD15 (2 mg/kg) has a half‐life of ~15 minutes in the circulation. Both doses of MF66 (0.5 and 2 mg/kg) were below detection. SPION’s accumulation was observed in the liver with MRI scans. Using Prussian blue staining, SPION’s were observed in the liver and spleen at higher doses and in the lungs at both doses. Our results suggest that further modifications may be required to enhance the biocompatibility of these particles in order to utilize them as diagnostic and therapeutic agents.Grant Funding Source: Framework Programme 7
All‐trans retinoic acid promotes fatty acid oxidation in human hepatoma (HepG2) cells (LB612)
Authors: Tripathy Sasmita , Arnold Samuel , Chapman John , Goodlett David , Isoherranen Nina 
Published: June 2021

It has recently emerged that retinoic acid (RA) acts as a ligand for peroxisome proliferator activated receptor (PPAR), a master nuclear receptor of lipid metabolism, in addition to the retinoic acid receptor. The role of all‐trans‐RA (atRA) on regulating lipid metabolism is, however, not clearly understood. In the present study, we examined the effect of atRA on fatty acid oxidation (FAO) in human hepatoma (HepG2) cells. HepG2 cells were cultured in presence or absence of atRA for 24 or 72 hrs, after which, cells were harvested to isolate RNA/protein to check gene/protein expression. Proteomics analysis performed on isolated protein after 72hrs of incubation with atRA showed that atRA significantly increased expression of key enzymes involved in FAO pathway such as acyl CoA dehydrogenase, long chain fatty acyl CoA ligase 3 and 4, delta (3, 5)‐delta (2, 4)‐dienoyl‐CoA isomerase and mitochondrial ATP synthase subunit alpha. Additionally, treatment with atRA significantly increased the mRNA of PPARδ, PPARα and its co‐activator PGC1α, and PPARα/δ target genes: CPT1α, PDK4 and FGF19, which all have role in FAO. Collectively, these results indicate that atRA promotes FAO via PPARα/δ induction in a dose dependent manner. Thus, our findings improve our understanding of RA role in lipid metabolism and signaling in liver.Grant Funding Source: Supported by NIH R01 GM081569 and GM081569‐S1
8’‐glycinil β‐carboline inhibits nitric oxide formation but not NF‐kB‐mediated inflammatory responses in macrophages (LB614)
Authors: Grodzki Ana , Gorin Fredric , Lein Pamela 
Published: June 2021

Neuropathic pain arising secondarily from an acute nerve injury is frequently associated with a protracted inflammatory response. While multiple inflammatory molecules, signaling pathways and neurochemical alterations contribute to chronic neuropathic pain, an essential role for nitric oxide generated by peripheral macrophages and microglia in the dorsal root ganglia and spinal cord has been reported. Specifically, the non‐selective nitric oxide synthase (NOS) inhibitor NG‐nitro‐L‐arginine methyl ester (L‐NAME) was reported to reduce thermal hyperalgesia in inflammatory pain models and selective blockers for constitutive NOS and inducible NOS have been shown to reduce inflammatory response and neuropathic pain. Here, as part of a screen for novel therapeutics for neuropathic pain, we studied the effects of a novel hydrophilic 8’‐glycinyl 6‐chloro beta carboline (8’‐Gly carb) on nitric oxide formation and NF‐kB activation in macrophages. Our data show that 8’‐Gly carb inhibits constitutive and inducible nitric oxide formation and interferes with NF‐kB‐mediated reporter. However, 8’‐Gly carb does not affect NF‐kB p65 subunit translocation to the nuclei or expression of pro‐inflammatory cytokines TNF and IL‐1β. Moreover, 8’‐Gly carb does not inhibit Erk 1/2 or P38 MAP kinase activity. Since 8’‐Gly carb significantly inhibits constitutive and inducible nitric oxide formation without interfering with downstream effects of NF‐kB, 8’‐Gly carb holds promise as an agent that might be used to reduce neuropathic pain in the face of chronic inflammation.Grant Funding Source: Supported by NIH/NIEHS ES017592
Impact of fatty acids on endothelial cell Cx43 expression (LB653)
Authors: Zucker Noah , Kurjiaka David 
Published: June 2021

Increases in the prevalence of obesity worldwide have prompted concerns of an upswing in atherosclerotic diseases. The dyslipidemia that characterizes obesity includes elevated circulating free fatty acids that contribute to atherosclerosis by compromising endothelial cell function. While there are many aspects of endothelial cell function, we focused on connexin 43 (Cx43) as hypertension and diabetes increase endothelial Cx43 expression. Since the epidemiological evidence argues for structure‐based differences in the atherosclerotic potential of fatty acids (cis protect vs trans promote), we evaluated the impact of fatty acid structure on endothelial cell Cx43 expression. First, we quantified endothelial cell (mouse bEnd.3: ATCC) responses to 4 fatty acids [saturated (steric) or unsaturated (oleic {cis}, linoleic {omega‐6}, and eladic acid {trans})]. After 24 hours at 0.3 to 300 μM, there was little change in endothelial cell Cx43 expression. However, treatment with 30 μM linoleic or oleic acid generated a biphasic response: Cx43 expression increased early (~3 hrs) and decreased later (~12 hrs). This time‐dependent response may reflect differences in the underlying mechanisms (prostaglandin synthesis vs receptor activation). Thus, preliminary data argue that endothelial Cx43 expression is altered by fatty acids although evidence for structure dependent difference is lacking.Grant Funding Source: Supported by Student Summer Scholars at GVSU
Leucine‐Rich Repeat Containing 10 (LRRC10) protein associates with and regulates the cardiac Cav1.2 L‐type calcium channels (LB693)
Authors: August Benjamin , Reynolds Courtney , Balijepalli Ravi 
Published: June 2021

Leucine‐rich repeat containing 10 (LRRC10) is a cardiac‐specific protein expressed in embryonic and adult hearts and plays critical roles in cardiac development and function. Recently we have demonstrated that the Lrrc10‐null (Lrrc10‐/‐) mice develop dilated cardiomyopathy and ventricular myocytes from Lrrc10‐/‐ mice exhibit reduced L‐type Ca2+ channel (LTCC) current (ICa,L) density. However, the precise role of LRRC10 protein in the regulation of LTCC function in the cardiomyocytes is unknown. To investigate the regulatory role of LRRC10 on Cav1.2 channel function, we co‐expressed the Myc tagged LRRC10 (LRRC10‐Myc), heamagglutinin tagged Cav1.2 (Cav1.2‐HA) and auxiliary Cavβ2CN4 subunit in HEK293 cells and performed co‐immunoprecipitation (co‐IP) on lysates using either anti‐HA, anti‐Myc antibody or control IgG. Western blot analysis demonstrated that Cav1.2 and LRRC10 associated with one another. Also, the auxiliary Cavβ2C subunit and LRRC10 did not co‐IP with one another suggesting that the LRRC10 may directly interact with the Cav1.2 subunit. A single point mutation H150A or triple point mutations Y104A, W127A and H150A mutation in LRRC10 disrupted the LRRC10 protein association with Cav1.2. Co‐IP analysis using mouse ventricular homogenates demonstrated that LRRC10 and Cav1.2 subunit are associated with one another. Additionally, double immunogold labeling and electron microscopy analysis revealed that LRRC10 and Cav1.2 proteins are co‐localized at T‐tubules in the ventricular myocytes. Finally, whole‐cell patch clamp experiments performed in ventricular myocytes from Lrrc10‐/‐ mice demonstrated a significant reduction in the ICa,L density (‐2.5 0.2 pA/pF) and compared to WT myocytes (‐6 0.6 pA/pF). Furthermore, the inactivation of the ICa,L in Lrrc10‐/‐ myocytes was significantly delayed. We conclude that LRRC10 protein is a novel and essential regulator of the LTCC function in ventricular myocytes.Grant Funding Source: R01HL105713
Ketogenesis prevents diet‐induced fatty liver injury and hyperglycemia through coenzyme A recycling (LB769)
Authors: Cotter David , Ercal Baris , Leid Jamison , D'Avignon D. Andre , Graham Mark , Dietzen Dennis , Brunt Elizabeth , Crawford Peter 
Published: June 2021

Nonalcoholic fatty liver disease (NAFLD) spectrum disorders affect approximately one billion individuals worldwide. The mechanisms driving progressive steatohepatitis remain incompletely defined. Here we use a murine model of mitochondrial 3‐hydroxymethylglutaryl CoA synthase (HMGCS2)‐deficiency (using anti‐sense oligonucleotides) to demonstrate a critical role for ketogenesis in prevention of diet‐induced steatohepatitis. Adult‐onset loss of HMGCS2 caused mild hyperglycemia and increased hepatic gluconeogenesis from pyruvate in chow‐fed mice. High‐fat diet (HFD) feeding of ketogenesis insufficient mice caused extensive hepatocyte injury and inflammation, decreased glycemia, deranged hepatic tricarboxylic acid (TCA) cycle intermediate concentrations, and impaired hepatic gluconeogenesis due to fatty acid‐induced sequestration of coenzyme A (CoASH). CoASH precursor supplementation (pantothenic acid and cysteine) normalized TCA intermediates and gluconeogenesis in ketogenesis insufficient livers. These findings identify ketogenesis as a critical regulator of hepatic glucose metabolism and TCA cycle function via coordination of CoASH homeostasis in the absorptive state and indicate that ketogenesis modulates fatty liver disease.Grant Funding Source: HG00668702, DK091538, DK020579, DK056341, HL007873
AMP‐activated protein kinase (AMPK) α1 is required for brown adipogenesis (LB843)
Authors: Yang Qiyuan , Liang Xingwei , Fu Xing , Rogers Carl , Zhu Meijun , Du Min 
Published: June 2021

Brown adipose tissue (BAT) burns fatty acids to generate heat, holding the promise to treat obesity and type 2 diabetes. However, mechanisms regulating brown adipocyte formation remain poorly defined. AMP‐activated protein kinase (AMPK) is a key regulator of energy metabolism. We hypothesized that AMPK regulates the development of brown fat, an important organ involved in energy catabolism. To test, we employed AMPKα1 floxed mice which were crossed with ER‐Cre mice to conditionally knockout AMPKα1. AMPKα1 knockout was induced by 4‐hydrotamoxifen. Abrogation of AMPKα1 blunted the brown adipogenic differentiation of stromal vascular cells isolated from brown fat. Correspondingly, the expression of UCP‐1 and Prdm16, two markers of brown adipogenesis, was pronouncedly suppressed during differentiation (around 4 fold and 3 fold reduction respectively, P = 0.03). Moreover, adipogenic progenitor cells were separated from brown stromal vascular cells by FACS using surface markers (sca1+/CD34+/CD45‐). Consistently, the absence of AMPKα1 blocked brown adipogenesis in purified progenitors. Taken together, these data suggest that the AMPKα1 is required for brown adipogenesis (The work was funded by NIH R01HD067449).Grant Funding Source: Supported by NIH R01HD067449
Aldosterone transcriptionally regulates large conductance K+ channel β1 (BKβ1)‐ subunit specific mRNA abundance in rat distal colon (LB845)
Authors: Sreekumar Shruthi , Rajendran Vazhaikkurichi 
Published: June 2021

Background: Large conductance K+ (BK) channels localized on the apical membranes mediate cAMP and aldosterone (“aldo”) activated K+ secretion in rat distal colon. BK channels composed of α (BKα) and β (BKβ) subunits. Four different BKβ (BKβ1, BKβ2, BKβ3 and BKβ4) isoforms have been shown expressed in tissue specific pattern. Recent studies have shown “aldo” transcriptionally up‐regulates BKα‐subunit. The identity of BKβ isoform and its regulation by “aldo” is not known in rat distal colon. Aim:This study was aimed: 1) to identify the BKβ isoform; and 2) to demonstrate whether BKβ subunit also transcriptionally regulated by “aldo” in rat distal colon. Methods: “Aldo” rats (Sprague‐Dawley, 200 ‐ 220 g) were produced by feeding Na‐freed diet ad libitum for 6 ‐ 7 days. Total RNA was purified from epithelial cells isolated form rat proximal and distal colon. BKβ isoform specific fragments were amplified using isoform specific primers and polymerase chain reaction (PCR). Quantitative RT‐PCR (RT‐qPCR) analyses were performed to quantify the expression level of BKβ.isoform in “aldo” rat distal colon. Results: PCR amplified BKβ1, but not BKβ2, BKβ3 and BKβ4 isoform specific fragments in both proximal and distal colon. RT‐qPCR analyses revealed that similar to BKα‐subunit, BKβ1‐subunit specific mRNA expression also enhanced by 3.5‐fold in “aldo” rat distal colon. The P‐values for BKβ1 subunit was less than 0.05 thus indicating a significant change at a 95% confidence. BKβ1‐subunit specific mRNA level is not altered in “aldo” proximal colon. Conclusions: Rat colonic BK channel consists of BKβ1 isoform; and 2) “Aldo” transcriptionally up regulates both BKα‐ and BKβ1‐subunits in distal, but not proximal colon.Grant Funding Source: West Virgina University Intramural award
Brain‐derived neurotrophic factor causes chloride gradient collapse in supraoptic neurons inducing vasopressin‐mediated blood pressure increase (LB847)
Authors: Choe Katrina , Han Su , Gaub Perrine , Shell Brent , Knapp Blayne , Barker Phillip , Brown Colin , Voisin Daniel , Cunningham J. , Bourque Charles 
Published: June 2021

Vasopressin (VP), an antidiuretic hormone, is also a potent vasoconstrictor and has been found at high levels in salt‐sensitive hypertensives. Hypertension normally reduces VP secretion by MNCs in the SON, by GABA‐dependent synaptic inhibition of their firing activities. However, in rats under chronic hypernatremia, GABAA receptor‐mediated synaptic inhibition is abolished in SON neurons due to a depolarization in chloride reversal potential (ECl), suggesting that continued VP secretion despite BP elevations may underlie the development of salt‐dependent hypertension. In order to test this hypothesis, we measured the mean arterial pressure (MAP) by radio telemetry in freely moving rats made chronically hypernatremic by 2% saline drinking. MAP of these rats rose steadily rise during the course of the 7‐day SL treatment (basal BP: 97.7±1.9 mmHg; day 7: 113.5±2.1 mmHg; n=10; P<0.05), however remained stable in euhydrated rats over the same time period (basal BP: 98.3±2.5 mmHg; day 7: 100.6±2.2 mmHg; n=6; P=0.50). Furthermore, the SL‐mediated increase in MAP was significantly reduced by continuous systemic infusion of a VP receptor type 1 (V1R) antagonist (αday 7; +8.8±2.5 mmHg; n=6) when compared to SL controls (α15.1±1.0 mmHg; n=10; P<0.05). These findings confirm our hypothesis that circulating VP contributes to increases in BP during chronic hypernatremia. Brain‐derived neurotrophic factor (BDNF) is a high‐affinity TrkB agonist previously shown to be responsible for chloride gradient collapse. In order to investigate this possibility in the SON, we induced a specific knockdown of this protein in SL rats in vivo by stereotaxic injections of adeno‐associated virus (AAV) containing BDNF‐shRNA into the SON. ECl measurements via Gramicidin perforated patch‐clamp revealed that this treatment significantly hyperpolarized the ECl of SON neurons (‐56.2±5.4 mV; n=10) when compared to values measured in SL rats injected with control AAV containing a scrambled sequence of shRNA (‐40.1±2.4 mV; n=7; p<0.05). These results strongly suggest that BDNF is the TrkB agonist responsible for producing the chloride gradient collapse in SON neurons under chronic hypernatremia, a phenomenon which potentially underlie the development of salt‐sensitive hypertension. Funding source: Canadian Institutes of Health Research.Grant Funding Source: CIHR
Lubiprostone (a prostone) slows the in vitro growth of colon adenosarcoma cells with low [NAD+] 15‐OH PGDH (LB856)
Authors: Cuppoletti John , Malinowska Danuta , Chakrabarti Jayati , Tewari Kirti , Ueno Ryuji 
Published: June 2021

Objective. Lubiprostone is a bicyclic fatty acid (prostone) which is used widely for treatment of chronic idiopathic constipation (CIC), opioid‐induced constipation (OIC) and constipation‐associated irritable bowel syndrome (IBS‐C). [NAD+]‐15‐OH PGDH (PGDH), which synthesizes endogenous prostones from prostaglandins, is a suppressor of human gastrointestinal cancers and genetic therapy with PGDH slowed the growth of colon tumor xenographs. The present study was to determine whether lubiprostone, acting as a prostone, would slow growth of colon cancer cells which express low PGDH and whether transfection of low PGDH colon cancer cells with PGDH would ablate the effects of lubiprostone on the cancer cells.Methods. LS174T (colon adenosarcoma) cells that contain low PGDH were grown in Eagle’s MEM/10% FBS, transfected with human PGDH cDNA in pCMV6‐Entry vector or vector alone using Lipofectamine and selected using G418 (200 µg/ml). PGDH:GAPDH levels were determined by densitometry of western blots. LS174T cells, non‐transfected and transfected with hPGDH or vector alone (mock) were grown in 35mm petri dishes (0.5x104 cells/ dish) to 40% confluence and then treated with either 0.1% EtOH‐0.01% DMSO (vehicle) or 100 nM lubiprostone. Every 24 h media were changed and fresh vehicle or lubiprostone added. DMSO and lubiprostone were from Sucampo. Cell growth was monitored by directly counting the cells in a randomly chosen field using a cell cytometer at 0, 24, 48, 72 and 96 h. Similar studies were carried out with HT‐29 colon cancer cells.Results. LS174 T cell growth was slowed or stopped by 100 nM lubiprostone. Transfection of LS174T cells with PGDH, but not mock transfection, prevented lubiprostone inhibition of cell growth. Similar results were found with H‐T29 colon cancer cells.Conclusions. These results demonstrate that lubiprostone will slow or prevent the growth of colon cancer cells which contain low 15‐OH PGDH. These results provide a rationale for further study in clinical trials.
The cold never bothered me anyway: RiAFP (LB95)
Authors: Arp Allison , Edwards Kristina , Hamann Bailey , Lesher Jordanne , Parfitt Kim , Varga Krizstina 
Published: June 2021

Antifreeze proteins (AFP) exist in a wide variety of cold adapted organisms including fishes, bacteria, and insects. This unusual molecule inhibits the growth of ice crystals by irreversibly adsorbing to the flat surface of existing ice particles with a complex mechanism. The protein warps the smooth surface of ice to prevent the addition of other water molecules to the crystal, allowing the organism to survive in subzero temperatures. Longhorn beetle (Rhagium inquisitor) AFP (RiAFP) is a hyperactive protein that binds to basal, as well as prism, ice surfaces. This multiple surface attachment results in a 10‐fold higher activity than AFP in fishes. RiAFP forms a compressed [[Unsupported Character ‐ Symbol Font β]]‐solenoid architecture consisting of two parallel 6‐ and 7‐stranded [[Unsupported Character ‐ Symbol Font β]]‐sheets. Two cysteines involved in a disulfide bridge link the [[Unsupported Character ‐ Symbol Font β]]‐sandwich fold. RiAFP has an exceptionally flat and large ice‐binding surface lined with a regular array of Thr residues that are spaced at the same distance as oxygen atoms in the ice surface, creating a surface complementarity to ice. AFP are of particular interest to researchers because of their many potential uses in cryopreservation, such as tissue storage and plant genetic engineering. The Central SMART Team (Students Modeling A Research Topic) modeled RiAFP using 3D printing technology.Grant Funding Source: Supported by grants from the NIH‐SEPA and NIH‐CTSA.
Associations between menopause, cardiac remodeling, and diastolic function: the CARDIA study
Authors: Ying Wendy , Post Wendy S. , Michos Erin D. , Subramanya Vinita , Ndumele Chiadi E. , Ouyang Pamela , Ambale-Venkatesh Bharath , Doria De Vasconcellos Henrique , Nwabuo Chike C. , Schreiner Pamela J. , Lewis Cora E. , Reis Jared , Lloyd-Jones Donald , Sidney Stephen , Lima Joao A.C. , Vaidya Dhananjay 
Published: June 2021

Abstract

Objectives:
Heart failure with preserved ejection fraction (HFpEF) affects more women than men. Menopause may influence HFpEF development in women. We assessed cross-sectional and longitudinal associations between menopause and echocardiographic measures of left ventricular (LV) function and cardiac remodeling.

Methods:
We studied 1,723 women with available echo data from at least two of: year 5 (Y5) (1990-1991), Y25 (2010-2011), or Y30 (2015-2016) in the Coronary Artery Risk Development in Young Adults study. Cardiac structure and function were measured using 2D and Doppler echocardiography. Cross-sectional associations between menopausal status and repeated echo measures at Y25 and Y30 were analyzed using linear mixed models. Two-segmented models were used to compare longitudinal changes in echocardiographic measures in the premenopausal period to changes in the postmenopausal period.

Results:
Mean ± SD age (years) at enrollment was 27 ± 3 in those with menopause by Y25, 25 ± 3 in those with menopause between Y25 and Y30, and 21 ± 3 in those premenopausal at Y30. There were no significant differences in race, body mass index, systolic blood pressure, or diabetes between the groups. Postmenopausal women had higher early diastolic mitral inflow (E) to annular (e’) velocity ratio than premenopausal after adjusting for demographics and risk factors (P < 0.05). Menopause was associated with relative increases in the rates of change in LV mass and left atrial volume, even after adjustment. Change in E/e’ ratio was similar before and after menopause.

Conclusions:
Menopause is associated cross-sectionally with worse diastolic function and longitudinally with adverse LV and left atrial remodeling. This may contribute to the increased HFpEF risk in postmenopausal women.

Video Summary:

http://links.lww.com/MENO/A787.