bluuebunny/crossref_metadata_2025_split huggingface dataset:
TRPV4 regulates P. gingivalis lipopolysaccharide‐induced exacerbation of oxidized LDL‐mediated foam cell formation
Authors: Rahaman Shaik , Gupta Nabyendu , Goswami Rishov 
Published: June 2021

P. gingivalis, a predominant causative agent of periodontitis, has been linked to lipid‐laden macrophage foam cell formation, a critical process in atherogenesis. Emerging data support a role for both a biochemical factor, e.g., lipopolysaccharides (LPS), and a mechanical factor, e.g., matrix stiffness, in regulation of macrophage function and atherogenesis. We have obtained evidence that TRPV4, a mechanosensitive channel of the transient receptor potential vanilloid family, is the likely mediator of P. gingivalis lipopolysaccharide (PgLPS)‐induced exacerbation of oxidized low‐density lipoprotein (oxLDL)‐mediated macrophage foam cell formation. Specifically, we found that: i) genetic deletion of TRPV4 or antagonism of its function by a chemical inhibitor blocked PgLPS‐induced exacerbation of oxLDL‐induced macrophage foam cell formation; ii) macrophage TRPV4 activity was increased in response to both PgLPS and pathophysiological range matrix stiffness, and iii) TRPV4 deficiency blocked PgLPS‐induced exacerbation of matrix stiffness‐induced macrophage foam cell formation. Mechanistically, we show that TRPV4 regulates PgLPS‐induced oxLDL uptake but not its cell surface binding in macrophages. Altogether, these findings identify a critical role for TRPV4 in regulating PgLPS‐induced exacerbation of macrophage foam cell formation by modulating uptake of oxLDL.Support or Funding InformationAHA (13SDG17310007), Startup grant from University of Maryland, NIH (1R01EB024556‐01), and NSF (CMMI‐1662776) grants to Shaik RahamanThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Functional analysis of a biflavone, as a novel inhibitor of TRPV4‐dependent macrophages foam cell formation
Authors: Rahaman Shaik , Alharbi Mazen , Goswami Rishov 
Published: June 2021

Cardiovascular disease is the number one cause of death in United States, and atherosclerosis, a chronic inflammatory disease, is the most dominant underlying pathology. Macrophages, an essential cell type in atherogenesis, are known to directly respond to changes to their surrounding mechanical environment. As TRPV4 (transient receptor potential channel of the vanilloid subfamily) channels can be sensitized by changes in matrix stiffness, we hypothesize that, TRPV4 may upregulate inflammatory/atherogenic macrophage functions. We performed a high‐throughput screening for antagonists of TRPV4 from a library of 2000 compounds using a fluorometric imaging plate reader (FLIPR)‐based Ca2+ influx assay; we identified ginkgetin, a biflavone, as a novel antagonist to TRPV4. Primary and secondary screening was performed with normal human dermal fibroblasts and mouse bone marrow derived macrophages (BMDMs) to assess the ability of ginkgetin and other candidates to inhibit TRPV4‐elicited Ca2+ influx after TRPV4 activation with its selective agonist GSK1016790. In our hand's, ginkgetin demonstrated an IC50 of 0.5 μM for inhibition of TRPV4‐elicited Ca2+ influx. We show that antagonism of TRPV4 channel by ginkgetin blocks oxidized LDL (oxLDL)‐induced macrophage foam cell formation in a concentration dependent manner. Mechanistically, we show that ginkgetin attenuated oxLDL uptake but not its cell surface binding in BMDMs. Altogether, our results show that ginkgetin is a novel inhibitor of TRPV4‐mediated macrophage foam cell formation by modulating uptake of oxLDL.Support or Funding InformationAHA (13SDG17310007), Startup grant from University of Maryland, NIH (1R01EB024556‐01), and NSF (CMMI‐1662776) grants to Shaik O RahamanThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Variable Surface Display and Post‐Translational Regulation of the Fungal Adhesin Epa1p
Authors: Raposo Colin , McElroy Kyle A , Mirecki Jarett , Fuchs Stephen M 
Published: June 2021

Infection by the fungal pathogen Candida glabrata is reliant on a collection of cell surface adhesins that play a variety of roles necessary for transmission, establishment, and cell proliferation. One particular adhesin, Epithelial Adhesin 1 (Epa1p), is responsible for binding to host tissue and biofilm formation, which is essential for fungal propagation. Epa1p structure consists of three domains: a C‐terminal GPI anchor for cell wall linkage, an N‐terminal intercellular binding domain responsible for epithelial cell binding, and a serine/threonine rich linker domain connecting these terminal domains. The linker domain contains a 40‐amino acid tandem repeat region which our lab has observed to be variable in repeat copy number between isolates from clinical sources. We expressed Epa1p with various repeat copy numbers in epa1Δ C. glabrata as well as in the related yeast, S. cerevisiae to determine how differences in repeat copy number affect Epa1p surface display and binding to human epithelial cells. Our initial data suggest that the processing of, as well as cell wall stability of, Epa1p is dependent upon the repeat copy number of Epa1p. We have also collected data, which suggest that Epa1p surface level is dependent on media growth conditions. Altogether our data demonstrate that Epa1p repeat copy number influences the properties of Epa1p and the adhesive characteristics of C. glabrata.Support or Funding Information1. Army Research Office grant W911NF16101752. Tufts Collaborates!3. 2018 ASBMB Undergraduate Research Award4. Tufts Summer ScholarsThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
FPT, a Novel 5‐HT7 and 5‐HT1A Partial Agonist, Treats Neuropsychiatric Symptoms Modeled in Fmr1 Knockout Mice
Authors: Armstrong Jessica , Mukherjee Munmun , Booth Raymond , Canal Clinton 
Published: June 2021

Fragile X Syndrome (FXS) is the leading monogenetic cause of intellectual disabilities and autism. Seizures, severe anxiety, and sensory hypersensitivity are also common in FXS. The central serotonin system can modulate these symptoms, and certain serotonin receptors are functionally linked with proteins known to be altered in FXS, suggesting targeting them may be therapeutic for FXS. We are developing (S)‐5‐(2′‐Fluorophenyl)‐N, N‐dimethyl‐1,2,3,4‐tetrahydronaphthalen‐2‐amine (FPT), a partial agonist at both 5‐HT7 and 5‐HT1A receptors, as a treatment for FXS and autism. We previously reported that FPT corrects repetitive behaviors and enhances social interactions—core symptom domains in FXS and autism—in wild‐type (WT) mouse models. Herein, we report the results of tests assessing the efficacy of FPT to improve behavioral phenotypes in Fmr1 knockout (KO) mice, an etiologically valid genetic model of FXS. Fmr1 KO mice have seizures when exposed to a 120 dB alarm (audiogenic seizures, AGS). 73% of vehicle‐treated Fmr1 KO mice we tested had AGS (males and females, age P23–25, N=22), however, 0% of the Fmr1 KO mice pretreated with FPT (5.6 mg/kg) had AGS (N=20). This effect was very significant (P<0.0001). In addition, FPT significantly reduced marble burying (vehicle, N=11, FPT, N=10, P<0.001) and reduced rearing in Fmr1 KO mice (vehicle, N=12, FPT, N=12, P<0.05). These data corroborate our earlier studies that FPT corrects repetitive behaviors and may have anxiolytic properties. We next tested FPT's efficacy to promote social behavior. Mice were matched for genotype and sex and paired together for a 10 minute observation period. One mouse was given vehicle and the other was given FPT. Social behavior, scored by an observer blind to treatment, was defined as the number of approaches from one mouse to the other and was recorded for each mouse within the pair. FPT increased social behavior in both WT (P<0.005) and Fmr1 KO (P<0.05) mice. We did not observe overt behavioral toxicity (for example, hypolocomotion, flat body posture, tremor, or head weaving) in mice treated with FPT. Our data provide further evidence that FPT has activity in neurobehavioral assays suggesting anxiolytic and prosocial effects that extend from WT to Fmr1 KO mice.Support or Funding InformationDOD W81XWH‐17‐1‐0329, FRAXA Research FoundationThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Crystal Structure of the C‐terminal Guanine Exchange Factor Module of Trio Reveals its Oncogenic Potential
Authors: Bandekar Sumit J. , Arang Nadia , Tully Ena S. , Tang Brittany A. , Barton Brenna L. , Li Sheng , Gutkind J. Silvio , Tesmer John J.G. 
Published: June 2021

The C‐terminal guanine exchange factor module of Trio (TrioC) activates the small G protein RhoA, linking Gαq/11‐coupled 7TM receptors to cellular events including cytoskeletal rearrangements and gene transcription. This signal transduction pathway underlies the development of uveal melanoma, a fatal malignancy. Previous studies have shown that TrioC is regulated via autoinhibition relieved by the binding of Gαq/11. However, the structural determinants of the autoinhibited state have remained elusive. We determined the crystal structure of TrioC in its basal state, revealing the molecular basis of autoinhibition mediated by the pleckstrin homology (PH) domain via direct interactions with the Rho binding site on the Dbl homology domain (DH). We show that truncation of the PH domain or introduction of point mutations activates the TrioC module in nucleotide exchange assays by liberating the Rho binding site. This model is consistent with results obtained by hydrogen‐deuterium exchange mass spectrometry. Finally, we show that mutations in the PH domain found in cancer patients also hyper‐activate full length TrioC in cell based models. These mutations may thus represent the first known cancer drivers in Trio that operate in an analogous, yet Gαq/11‐independent manner.Support or Funding InformationThis work was supported by NIH Grants CA221289, HL122416, and HL071818 (to J.J.G.T.), 5T32GM007767‐38, 5T32GM007767‐39, and F31CA224804 (to S.J.B.), and 5T32GM007752‐39 (to N.A.). This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE‐AC02‐06CH11357. Use of the LS‐CAT Sector 21 was supported by the Michigan Economic Development Corporation and the Michigan Technology Tri‐Corridor (Grant 085P1000817).This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Sex‐dependent responses to norditerpenoid alkaloids from Delphinium in Angus cattle
Authors: Green Ben , Welch Kevin , Pfister James , Davis Zane , Stonecipher Clint , Cook Daniel 
Published: June 2021

Plants produce bioactive secondary chemical compounds which are not involved in metabolism, photosynthesis or reproduction. Norditerpenoid alkaloids produced by Delphinium spp. (larkspur) poison cattle grazing on rangelands of western North America. The objective of this study was to compare the physiological responses of yearling and two year old Angus heifers, steers, and bulls with a standardized dose of norditerpenoid alkaloids in the form of dried ground Delphinium barbeyi. Clinical signs of intoxication, including loss of muscle coordination and function were measured 24 h after oral dosing with larkspur by walking the cattle at a pace of 5–6 km/h for up to 40 min on an oval dirt track. The walk times of the yearling cattle were: 2.9 ± 1.2 minutes (30 heifers), 16.6 ± 1.9 minutes (60 steers), and 15.5 ± 2.4 minutes (33 bulls). Two‐year old heifers walked 6.7 ± 3.3 minutes (15 heifers). Serum alkaloid concentrations were measured immediately prior to walking, and deltaline concentrations averaged 266 ± 28, 131 ± 20, and 219 ± 28 ng/mL for all heifers, steers and bulls, respectively, and serum methyllycaconitine concentrations averaged 660 ± 46, 397 ± 32, and 612 ± 34 ng/mL for all heifers, steers and bulls, respectively. These results suggest that yearling and two year old Angus heifers are more susceptible to larkspur intoxication than bulls or steers.Support or Funding InformationSupported by USDAThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Next Generation Potent Cell‐active Inhibitors of the Oncogenic PTP4A3 Phosphatase
Authors: Blanco Isabella K. , Tasker Nikhil R. , Rastelli Etttore J. , Wipf Peter , Sharlow Elizabeth R. , Lazo John S. 
Published: June 2021

High grade serous ovarian cancer and triple negative breast cancer respond poorly to existing drugs and, thus, demand new therapies. The protein tyrosine phosphatase PTP4A3 (Phosphatase of Regenerating Liver‐3, PRL‐3) is overexpressed in these diseases. Moreover, PTP4A3 promotes cancer cell migration and invasion and is believed to be the most oncogenic of all tyrosine phosphatases. We recently synthesized the novel iminothienopyridone, JMS‐053, and demonstrated that it is a specific, reversible, allosteric, and cell active small molecule PTP4A3 inhibitor with an in vitro IC50 for PTP4A3 of 30 nM. The water solubility of JMS‐053 is limited, however. Therefore, we synthesized twenty next generation analogs to improve aqueous solubility and to aid in determining the structure activity relationship for the chemotype, the PTP4A3 binding site, and the mechanism of inhibition. Seventeen analogs retained potent in vitro PTP4A3 inhibition with IC50 values <100 nM. Four compounds, EJR‐866‐36, EJR‐866‐68, EJR‐855‐81, and NRT‐892‐04, had in vitro PTP4A3 IC50values of <40 nM. EJR‐866‐75 and NRT‐870‐59 were computationally more drug‐like than JMS‐053. EJR‐855‐81, NRT‐870‐59, EJR‐866‐75, and NRT‐870‐59 were cytotoxic to human Hs578T breast cancer and OVCAR4 ovarian cancer 3D spheroid tumor cells grown in vitro with IC50 values below 20 mM. To further expand the mechanistic activity of this class of inhibitors, we have synthesized four third‐generation analogs of JMS‐053, which combine the iminothienopyridone motif with a chemical moiety capable of binding a E3 ubiquitin ligase that will accelerate the intracellular degradation of PTP4A3. One of these novel compounds, EJR‐887‐35, had a PTP4A3 in vitro IC50 value of 107 nM and retained cytotoxicity to Hs578T and OVCAR4 cells with IC50 values below 20 mM in 3D spheroid tumors. These results suggest the iminothienopyridone chemotype could be valuable for the development of the first potent, cell active PTP4A3 phosphatase inhibitors directed against breast and ovarian cancer.Support or Funding InformationDepartment of Defense (Award W81XWH‐18‐1‐0011, BC170507), NIH Grant P30 CA044579 and S10 OD021723, and the Fiske Drug Discovery Fund.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 Mechanism of Inhibition of the Undrugged Oncogenic Phosphatase PTP4A3 by a Novel Small Molecule JMS‐053
Authors: Garrott Sharon R. , Blanco Isabella K. , Tasker Nikhil R. , Rastelli Ettore J. , Sharlow Elizabeth R. , Wipf Peter , Lazo John S. 
Published: June 2021

The oncogenic tyrosine phosphatase PTP4A3 is an attractive cancer therapeutic target because it is overexpressed in many types of cancer and promotes tumor metastasis, contributing to poor patient prognosis. We recently synthesized JMS‐053, which is a potent, selective, reversible, iminothienopyridinedione inhibitor of PTP4A3. We modeled possible interactions between JMS‐053 and PTP4A3 and the goal of our current work was to test the model and further define the crucial amino acids involved in the PTP4A3 inhibition by JMS‐053. We generated three PTP4A3 single amino acid mutants: C104S, K144I and C49S. The enzymatic activities of these phosphatases were determined in vitro in the absence and presence of JMS‐053, using the artificial substrate 6,8‐difluoro‐4‐methylumbelliferyl phosphate. The C104S mutant showed no catalytic activity, consistent with C104 being the catalytic cysteine. The K144I mutant retained full enzymatic activity. In contrast to our molecular modeling predictions, the K144I mutant was inhibited by JMS‐053 to the same extent as the wild type enzyme. We concluded K144 was not primarily involved in JMS‐053 inhibition. Tyrosine phosphatases are known to be inhibited by intramolecular disulfide bond formation and C49S has been reported to be the only cysteine involved with disulfide bond formation with the catalytic C104. The C49S mutant had reduced catalytic activity compared to the wild type PTP4A3 but JMS‐053 retained partial inhibition. Thus, C49‐C104 disulfide bond formation does not appear to be the primary mode of JMS‐053 inhibition, although we cannot completely exclude involvement of C49. We are now examining the oxidation state of C104 after JMS‐053 treatment and new analogs of JMS‐053. The information obtained from mapping the critical amino acids involved in PTP4A3 inhibition should assist in the design of the next generation phosphatase inhibitors.Support or Funding InformationThe Department of Defense (BC170507), the Fiske Drug Discovery Fund and the Ivy Foundation.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Phospholipids as Indicators of Docetaxel‐Resistant Castration‐Resistant Prostate Cancer
Authors: Ingram Lishann M , Mansoura Maryam , Cummings Brian S 
Published: June 2021

The association of circulating lipids with clinical outcomes of drug‐resistant castration‐resistant prostate cancer (CRPC) is not fully understood. While it is known that increases in plasma lipids correlates to decreased survival, neither the mechanisms mediating alterations in these lipids nor the correlation of resistance to treatment are well characterized. We addressed this gap‐in‐knowledge using in vitro models of non‐cancerous, hormone sensitive, CRPC and drug‐resistant cell lines combined with quantitative HPLC‐ESI‐Orbitrap‐MS lipidomic analysis. HPLC‐MS based metabolomic analysis identified 83 features that were significantly altered in the drug‐resistant cell lines as compared to non‐resistant control group. Within the 83 species, two were identified as individual plasma lipid biomarkers for diagnosis of prostate cancer from previous studies. Principal component analysis (PCA) demonstrated that drug‐resistant and control cell‐lines were visually separated by these identified lipid biomarkers. Two out of the 83 lipid classes were identified as phosphatidylcholine (PC) 18:0/18:1 and PC 18:0/18:2), both of which had high level of abundance in Docetaxel‐resistant CRPC. An untargeted approach indicated that lipids corresponding to PC, phosphatidylglycerol (PG), phosphatidic acid (PA) and phosphatidylserine (PS) all had higher relative abundance in DR‐CRPC cells (DU145‐DR) compared to parent control (DU145). These data suggest that the lipidomic profiles of prostate cancer cells lines recapitulate lipidomic profiles in the plasma of prostate cancer patients. As such, these metastatic dependent and drug‐resistant cell lines may prove useful for understanding the molecular mechanisms mediating lipid changes in prostate cancer patients.Support or Funding InformationNational Institute of Biomedical Imaging and Bioengineering NIBIB (EB0160100) Department of Defense Prostate Cancer Research Program Idea Development Award (PC150431 GRANT11996600)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
A Potassium Channel Blocker, 4‐Aminopyridine, Attenuates Peripheral Nerve Injury‐induced Muscle Atrophy, Improves Intrinsic Muscle Force, and Suppresses the Expression of Muscle Atrophy‐related Transcription Factors in Mice
Authors: Talukder MA Hassan , Yue Li , Noble Mark , Dirksen Robert , Chakkalakal Joe , Elfar John C 
Published: June 2021

4‐Aminopyridine (4‐AP), a broad‐spectrum potassium channel blocker and FDA‐approved drug for the symptomatic treatment of multiple sclerosis, is used to improve neuromuscular function in patients with diverse demyelinating disorders. The neurological benefits of 4‐AP are believed to result from increases in action potential duration, calcium influx, neurotransmitter release and synaptic transmission. Traumatic peripheral nerve injury (TPNI) represents a major health problem that often leads to significant functional impairment and permanent disability from the loss in axonal continuity, neuronal cell death, nerve demyelination, nerve conduction defects, muscle denervation, and muscle atrophy. We have recently repurposed the use of 4‐AP and demonstrated that systemic 4‐AP administration enhances global functional recovery of the affected limb, promotes remyelination of the nerve and improves the nerve conduction velocity in a mouse model of TPNI. While muscle atrophy occurs very rapidly following nerve injury, the effect 4‐AP on muscle atrophy and muscle contractile function is largely unknown. This study was designed to explore the possible beneficial effects of 4‐AP treatment in muscle atrophy, intrinsic muscle function, and muscle regeneration following acute sciatic nerve crush injury. Mice were assigned to moderate sciatic nerve crush injury and no‐injury groups and followed for 3, 7 and 14 days with/without 4‐AP (10 mg/daily, intraperitoneal injection) or saline treatment. Morphological, functional and transcriptional properties of skeletal muscle were assessed. In addition to improving in vivo global motor function as early as post‐operative day 3, 4‐AP treatment significantly attenuated muscle atrophy of the injured limb with increased muscle mass and muscle fiber area. 4‐AP also improved ex vivo intrinsic muscle contractile force 7 days post‐injury. Most importantly, the reduced muscle atrophy with 4‐AP treatment was concurrent with significantly reduced expression of atrophy‐related genes (myogenin, MuRF‐1, FoxO1, FoxO3) and increased expression of Pax7+ satellite cells and proliferating Ki67+ cells. These findings provide new insights into the beneficial effects of 4‐AP in nerve injury‐induced muscle atrophy and dysfunction and open a new window for further investigation.Support or Funding InformationThis work was supported by grants from the NIH (K08 AR060164‐01A) and DOD (W81XWH‐16‐1‐0725) in addition to institutional support from the University of Rochester and Pennsylvania State University Medical Centers.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.