bluuebunny/crossref_metadata_2025_split huggingface dataset:
Targeting Human DNAJAs for Sensitization to Chemotherapeutic Agents
Authors: Whitmore Aurellia 
Published: November 2023

PurposeBreast cancer is the second leading cause of cancer death among women in the US, with 20% of breast cancers being Triple Negative Breast Cancer (TNBC) which occur more often in African Americans and younger women.Despite considerable advances in targeted cancer therapy, many tumors including TNBC tumors either lack druggable targets or they lose them during cancer progression. For this reason, cytotoxic chemotherapy aimed at cellular proliferation continues to play an important role in the treatment of many neoplasias. First line of therapy for TNBC include agents such as anthracycline antibiotics, which albeit being effective are associated with serious side‐effects. Furthermore, drug resistance can develop during the course of treatment, which cannot be overcome by increasing the therapeutic dose. Preliminary studies in the eukaryotic model organism S. cerevisiae, have identified YDJ1, which encodes a heat‐shock 40 protein (HSP40), as an important factor in the cellular response to chemotherapeutic agent doxorubicin. Mutants of the YDJ1 gene display >100‐fold increased sensitivity to doxorubicin. In mammalian cells, the DNAJA group of HSP40 proteins, which includes DNAJA1, DNAJA2, DNAJA3 and DNAJA4, are more closely related to YDJ1. To determine the role of DNAJAs and target them for sensitization in the cellular response to cytotoxic drugs, we investigated their ability to rescue ydj1 mutants from exposure to chemotherapeutic agents.Design MethodsMutant strains complemented by the DNAJAs were exposed to chemotherapy agents: doxorubicin, and etoposide, as well as oxidative stress agent menadione.ResultsOur results indicate that the different DNAJAs provide distinct levels of protection, with DNAJA1 and DNAJA2 being more effective at complementation while DNAJA3 and DNAJA4 being less effective. In addition, the level of complementation was also dependent on the agent used.ConclusionComplementation with DNAJA2 was effective to rescue the response to cellular stress of doxorubicin and menadione, with no major contribution in the response to etoposide. These data indicate that the DNAJAs play a role in the protection of cells from cytotoxic stress and may serve as targets to hypersensitize cells to cancer therapy, allowing for treatment with lower dose with a concomitant reduction of side effects.Support or Funding InformationThis research is funded by the National Institute on Minority Health Disparities of the National Institute of Health under Award# P20MD006738, NIH‐RCMI Grant# 2G12RR003020 and the NMHHD, NIH 8G12MD007582‐28.
Epigenetic Regulation of Prostate Normal and Cancer Cell Lines
Authors: Korkmaz Ceren Gonen , Reel Buket , Arun Mehmet Zuhuri , Yildirim‐Buharalioglu Gokce 
Published: November 2023

Epigenetic investigates gene expression modifications not due to DNA sequence alterations. Gene expression modifications appear with packing of DNA with variety of chromatine structures. The most studied forms of epigenetic phenomenon are DNA methylation and histone modifications. These pathways are connected with each other and reversible.DNA methylation reported genes: 36B4 (as control), AR, HN1, PTEN, KLLN, STAMP1, STAMP2 primers were used and methylation status had been confirmed at normal WPMY‐1 prostate and lymhp node metastasis LNCaP and brain metastasis DU145 cancer cell lines, respectively. Histone modification which close the gene expression is histone deacetylation had been reversed by Trichostatin A(TSA). It is reported that inhibition of methylation and deacetylation in a serial way result with succesful gene activation, performed with 5‐Azacitidine and TSA incubation at the project. In the recent years, epigenetic base had been shown for many diseases that research and development for epigenetic disorders won successful treatment cases. Preclinic and clinic levels of candidate drugs are on the way.Support or Funding InformationEGE UNIV. SCIENTIFIC RESEARCH PROJECT
Camptothecin Sensitizes Refractory Lung Cancer Cells to Receptor Kinase Inhibitor
Authors: Almutairy Bandar Saeed , Andey Terrick 
Published: November 2023

BackgroundReceptor tyrosine kinases (RTKs) represent a large class of receptors that are upregulated in many cancers. The Ephrin‐A type‐2 precursor (EphA2) is an important RTK whose overexpression in lung cancer promotes growth, metastasis and acquisition of resistance phenotypes to therapies. Further, EphA2 is a downstream target of the epidermal growth factor receptor (EGFR) which is transcriptionally regulated by the oncogenic SOX2 transcription. This study investigates the effect of combination treatment with camptothecin (CPT) and the RTK inhibitor (RTKI) drug Erlotinib (Erl) in inhibiting survival mechanism in lung cancer cells.MethodsCell viability of H1299 and H1975 was determined using the Resazurin dye assay following single and combination treatments with CPT and Erl for 72 hours. The effect of 48‐hour single and combination CPT (1.0 μM) and Erl (10 μM and 20 μM) treatments on H1299 cell migration, apoptosis, and protein expression were investigated by wound healing assay, acridine orange‐ethidium bromide (AO‐EB) staining, and western blot respectively.ResultsH1299 and H1975 were resistant to Erl treatment (concentrations that killed 50% of cells, IC50 = 291.14±15.84 μM and 92.06±10.06 μM respectively). CPT was relatively more potent in inhibiting H1299 cell proliferation (IC50 = 7.01±0.35 μM). CPT co‐treatment at concentrations of 0.1 μM and 0.5 μM with different concentrations of Erl inhibited H1299 cell proliferation by 2‐(IC50 = 137.12±13.53 μM) and 10‐fold (IC50 = 27.88±2.88 μM) respectively. Combination treatment with CPT and Erl induced apoptotic events and inhibited H1299 cell migration compared to control and single treatment 48 hours after treatment. Additionally, SOX2 and c‐Myc expression as well as EphA2‐mediated cell migration signaling (phospho‐EphA2 Tyr588 and Tyr594 expression) were abrogated.ConclusionCPT is a potent, but highly toxic anticancer agent whose clinical utility is hindered by adverse dose‐dependent hematopoetic and other adverse effects. In this study, however, sub‐toxic doses of CPT was effective in sensitizing highly resistant H1299 cells to Erl through inhibition of cell migration and induction of apoptosis. Combination treatment with low‐dose CPT may be a viable means of sensitizing refractory cancer cells to therapy.Support or Funding InformationDr. Terrick Andey MCPHS UniversityE‐mail address:Terrick.andey@mcphs.edu
Altered Fatty Acid and Mitochondrial Metabolism in the Liver of Pregnant Adiponectin‐Deficient Mice Contributes to Insulin Resistance and Gestational Diabetes Mellitus
Authors: Moyce Brittany L , Cole Laura K , Xiang Bo , Fonseca Mario A , Hatch Grant M , Doucette Christine , Dolinsky Vern 
Published: November 2023

IntroductionGestational diabetes mellitus (GDM) is a common pregnancy‐related health condition. While genetics, lifestyle and diet contribute to development of GDM, evidence suggests that low levels of adiponectin increases the risk for GDM. Adiponectin is a fat derived hormone that improves the sensitivity of tissues to insulin. We hypothesize that adiponectin deficiency causes fatty liver during pregnancy, ultimately contributing to the development of GDM.MethodsWe compared the glucose and insulin tolerance of pregnant (3rd trimester) adiponectin−/− (strain B6;129‐Adipoqtm1Chan/J) and wild‐type mice, and assessed parameters of hepatic metabolism, including mitochondrial function and fatty acid metabolism. We assessed the impact of adiponectin supplementation by administering adenovirus mediated full length adiponectin at the end of the second trimester of pregnancy, and comparing to control containing GFP.ResultsIn the third trimester, pregnant adiponectin−/− mice exhibited fasting hyperglycemia regardless of diet (9.2mmol/L vs. 7.7mmol/L in controls, p<0.05). These mice display impaired glucose and insulin tolerance relative to wild‐type controls. Pregnant adiponectin−/− mice develop hepatic steatosis, including a 3‐fold elevation in hepatic triglycerides (p<0.05). This was associated with altered hepatic lipid metabolism, including a 2.5 fold increase in fatty acid synthase expression (p<0.05), elevated circulating free fatty acids, triglycerides and cholesterol. Nearly 2‐fold reduction (p<0.05) in maximal mitochondrial respiration was observed via oxidative flux analyzer in hepatocytes of adiponectin −/− mice. Hepatocytes from pregnant adiponectin−/− mice show dramatically reduced respiratory capacity when using fatty acids alone, and display elevated synthesis and secretion of triglycerides and cholesterol. Gestational weight gain and food consumption were similar in knockout and wild‐type mice. Adiponectin supplementation to pregnant adiponectin−/− mice significantly improved glucose tolerance, prevented fasting hyperglycemia, and attenuated fatty liver development.ConclusionResults show that adiponectin deficiency is associated with altered hepatic lipid metabolism and hepatic steatosis during pregnancy. Consequently, adiponectin deficiency contributes to mid‐gestation insulin resistance and hyperglycemia characteristic of GDM. Moreover, adiponectin supplementation rescues the effects of adiponectin deficiency on insulin sensitivity and hepatic lipid metabolism.Support or Funding InformationResearch Manitoba, Children's Hospital Research Institute of Manitoba
Interleukin‐18 is Crucial for the Development of Renal Inflammation and Elevated Blood Pressure in a Mouse Model of Hypertension
Authors: Ling Yeong Hann , Thomas Jordyn , Krishnan Shalini Murali , Ferens Dorota , Masters Seth , Kemp‐Harper Barbara , Mansell Ashley , Sobey Christopher , Drummond Grant 
Published: November 2023

BackgroundInterleukin‐18 (IL‐18) is a cytokine released downstream of inflammasome activation that promotes pro‐inflammatory TH1 immune responses. Clinical studies have shown that levels of IL‐18 are elevated in hypertensive patients. However, whether IL‐18 plays a causal role in hypertension is unknown.AimsTo determine if IL‐18 and/or its receptor (IL‐18R) are upregulated in kidneys of hypertensive mice and to establish if IL‐18 deficiency protects mice against the development of hypertension and renal inflammation.MethodsHypertension was induced in male wild‐type and IL‐18−/− mice by uninephrectomy and treatment with deoxycorticosterone acetate (2.4 mg/d, s.c.) and 0.9% NaCl in the drinking water (1K/DOCA/salt). Control mice received uninephrectomy, a placebo pellet and normal drinking water (1K/placebo). Systolic blood pressure (BP) was measured by tail cuff. After 21 days, kidneys were harvested to assess: renal hypertrophy; expression of IL‐18, IL‐18R, and the inflammatory markers ICAM‐1, VCAM‐1, CCL5 and CCL2 by real‐time PCR; and immune cell numbers and cellular expression of IL‐18R by flow cytometry.Results1K/DOCA/salt‐treated mice displayed elevated BP and kidney weights (140±3 mmHg; 390±8 mg) compared to 1K/placebo mice (118±2 mmHg; 291±7 mg; n≥17, P<0.05). 1K/DOCA/salt treatment also caused renal inflammation as indicated by ≥2‐fold increases in CD45+ leukocyte numbers, and expression of ICAM‐1, VCAM‐1, CCL5 and CCL2 (n≥7, P<0.001). IL‐18 expression was ~2‐fold higher in the kidneys of 1K/DOCA/salt versus 1K/placebo mice (n≥7; P<0.01). IL‐18R expression was also elevated by 3‐fold (n≥6; P<0.0001) with infiltrating CD4+ T cells representing the major cell type expressing this receptor. Importantly, IL‐18−/− mice were profoundly protected from the hypertensive actions of 1K/DOCA/salt compared to wild‐type mice (119±6 vs 145±6 mmHg; n=5, P<0.05) and displayed marked reductions (i.e. >2‐fold) in renal expression levels of ICAM‐1, VCAM‐1 and CCL2 (n≥4, P<0.05).ConclusionUpregulation of IL‐18 and its receptor is a major driver of renal inflammation and the development of hypertension following 1K/DOCA/salt‐treatment in mice. Hence, these findings highlight the IL‐18 signalling system as a potential target for future anti‐hypertensive therapies.Support or Funding InformationNHMRC Project Grant APP1041326
Molecular Mechanisms of the Protective Effects of Calcium Channel Blockers against Cyclosporine Nephrotoxicity in Rats
Authors: Hammoud Safaa H , Eid Assaad A , Omar Amal G , El‐Mas Mahmoud M 
Published: November 2023

Nephrotoxicity is a serious side effect for the immunosuppressant drug cyclosporine (CSA). In this study, we tested the hypothesis that the concurrent administration of calcium channel blockers such as verapamil or nifedipine guard against renal dysfunction induced by CSA in rats. Studies were then extended to investigate the roles of inflammatory, oxidative, and fibrotic pathways in the interaction. Six groups of male rats (n=6 each) were employed and allocated to receive one of the following treatments for 7 consecutive days: vehicle (cremophor), CSA (25 mg.kg−1.day−1), verapamil (2 mg.kg−1.day−1), nifedipine (3 mg.kg−1.day−1), CSA plus verapamil, or CSA plus nifedipine. Biochemical and histomorphometric analyses showed that compared with respective vehicle values, rats treated with CSA exhibited clear signs of nephrotoxicity that included: (i) proteinuria and elevations in serum creatinine and blood urea nitrogen, (ii) deposition of collagen IV in glomerular and tubular areas, and (iii) increases in the glomerulosclerosis index. While the single administration of nifedipine or verapamil caused no specific renal effects, the concurrent use of either calcium channel blocker significantly and equipotently ameliorated the biochemical and morphological derangements caused by CSA. We also report that the inflammatory (NF‐κB expression), oxidative (NADPH‐oxidase activity, reactive oxygen species production), and fibrotic (TGF‐β1 expression) manifestations of renal toxicity induced by CSA were eliminated upon concurrent administration of nifedipine or verapamil. Together, these results highlight the usefulness of calcium channel blocking agents in negating the CSA‐induced nephrotoxicity and predisposing biochemical and molecular machinaries.Support or Funding InformationSupported by the Lebanese National Council for Scientific Research (CNRS) Grant Award for Lebanese graduates (Awardee: Safaa Hammoud)
Diapocynin is less potent than Apocynin to induce vasodilation effect in blood vessels from normotensive rats
Authors: Potje Simone , Troiano Jessica Antonini , Graton Murilo Eduardo , Ximenes Valdecir Faria , Nakamune Ana Claudia , Antoniali Cristina 
Published: November 2023

IntroductionNicotinamide adenine dinucleotide phosphate oxidase (NAD(P)H oxidase) is a multicomponent enzyme system that generates superoxide anion by one‐electron reduction of molecular oxygen and represents the major source of reactive oxygen species (ROS) in the vascular cells. Apocynin has been extensively used as an inhibitor of NAD(P)H oxidase (NOX) in phagocytic cells. In phagocytes cells, due to the presence of myeloperoxidase, apocynin can be the converted to diapocynin, which is supposed to be the active form of this phytochemical. In non‐phagocytic cells, MPO is not expressed, the conversion of apocynin to diapocynin was suggested by hydrogen peroxide in human airway cells. Moreover, while apocynin induces anti‐hypertensive effect in spontaneously hypertensive rats (SHR) and vasodilatation in normotensive rats and SHR, there are no studies showing the effects of diapocynin on rat's blood pressure or vascular cells. We hypothesized that diapocynin induces hypotension and vasodilation in rats.MethodsWe tested chemically synthesized diapocynin and analyzed its antioxidant capacity and its effect on blood pressure and vascular reactivity in normotensive rats. We evaluated the levels of nitric oxide (NO), ROS and calcium in aortic endothelial cells stimulated by diapocynin. All results were compared to apocynin.ResultsDiapocynin showed higher antioxidant capacity in vitro than apocynin. Apocynin and diapocynin promoted hypotensive effects without changing the heart rate, however the effect of diapocynin on blood pressure was short‐lived when compared to the effect of apocynin. Diapocynin, as apocynin, induced endothelium‐independent vasodilatation in mesenteric resistance arteries from Wistar rats, however endothelium improved diapocynin vasodilator effect. In blood vessels, apocynin is more potent than diapocynin. Apocynin and diapocynin increased NO and decreased ROS levels in endothelial cells, however diapocynin did not alter calcium levels in these cells.ConclusionWe showed for the first time that diapocynin induces hypotensive and vasodilator effects in rats. Moreover, as apocynin, diapocynin increases NO‐bioavailability in blood vessels. The mechanisms involved in diapocynin effect are being evaluated.Support or Funding InformationFinancial support: Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) [Grant 141323/2013‐2].
FTDP‐17 mutants S320F and S352L have subtle differential effects on 4R tau isoform aggregation in vitro
Authors: Yenjerla Mythili , Gamblin Chris T 
Published: November 2023

Frontotemporal Dementia with Parkinsonism linked to chromosome‐17 (FTDP‐17) is a class of inherited neurodegenerative diseases caused by mutations in the tau gene. Tau protein is a microtubule associated protein that stabilizes microtubules in neurons. During neurodegeneration, tau protein aggregates to form toxic filaments. Tau isoforms have either three or four 18‐amino acid microtubule binding repeats, known as 3‐repeat tau (3R tau) or 4‐repeat tau (4R tau). The 4R and 3R tau isoforms are further classified into 0N, 1N and 2N isoforms based on the number of N‐terminal exons. Forty four different mutations in various positions of the tau gene have been reported. FTDP‐17 tau mutants 2N4R S320F and S352L cause neuropathology through different mechanisms of tau aggregation. The mutant S320F forms short tau oligomers while S352L forms long tau filaments in vitro. Here, we determined whether the 4R tau isoforms (0N, 1N, 2N) of S320F and S352L affect tau aggregation differently in vitro. We used right angle laser light scattering, thioflavin S florescence assay and transmission electron microscopy (TEM) to study arachidonic acid induced tau aggregation. All wild type 4R tau isoforms (0N, 1N, 2N) showed the same effect on polymerization of tau into filaments upon addition of arachidonic acid. All S320F isoforms (0N, 1N, 2N) showed a significant decrease (p < 0.01) and S352L isoforms (0N, 1N, 2N) showed no significant change in laser light scattering when compared to the corresponding wild type 4R isoforms. However, S320F isoform 1N showed a significant decrease (p < 0.01) in percentage change from the respective wild type isoform when compared to 0N, 2N S320F by one way ANOVA analysis of laser light scattering. S320F isoforms 0N, 2N showed an increase (p < 0.05, 0.01) and 2N S352L also showed an increase (p < 0.001) in thioflavin S fluorescence when compared to the corresponding wild type 4R isoform. TEM images of all 4R S320F filaments showed very short tau fibrils which could be tau oligomers while all S352L filaments showed an increase in length of tau polymer. The 2N S352L filaments were longer than filaments from 0N and 1N isoforms. Though the mutant isoforms have the same effect on tau polymerization, the extent of polymerization varies. These results show that the presence of N‐terminal exons have small, but significant, alterations in the pro‐aggregation properties of FTDP‐17 4R tau.Support or Funding InformationNIH grant R01NS083391
Using Small Angle X‐ray Scattering to determine the role of Poly‐cystic kidney disease‐like domains in Clostridium histolyticum
Authors: Caviness Perry Carter , Koide Takaki , Matsushita Osamu , Sakon Joshua 
Published: November 2023

Clostridium histolyticum is a bacterium that produces two collagen dismantling enzymes, i.e. Col H and Col G. Both collagenases have multi‐domain structures consisting of a catalytic module (S1) Polycystic kidney disease‐like domains (PKDs: S2A and S2B for Col H, S2 in Col G), named for containing the V‐set Ig fold first found in the polycystic kidney disease protein and collagen binding domains (CBDs: S3 for Col H, S3A and S3B for Col G). The three PKD domains are structurally similar and bind to one calcium ion. It is unknown what role the PKD domain plays in both Col H and Col G. Collagen binding assays for S2BS3 and S3 revealed that S2BS3 binds to collagen in two steps. S2BS3 was also shown to bind tighter to collagen than S3. PKD domains for Col H contain surface aromatic residues, similar to the collagen binding cleft for CBD. It is speculated that the surface aromatic residues on S2A (Tyr689 and Phe712) and S2B (Tyr780, His782, Tyr796 and Tyr801) assist in collagen binding. S2 lacks surface aromatic residues suggesting that it is a spacing domain. Small angle x‐ray scattering (SAXS) samples were prepared for S2AS2BS3, S2BS3 and S2S3AS3B with each bound mini‐collagen. After data collection envelopes were prepared. Solved crystal structures of each segment were fit into the SAXS envelope. S2B was found to make contact with the mini‐collagen while S2 did not make contact. Site directed mutagenesis of surface aromatic residues on S2B will need to be performed to confirm their role in collagen binding. A fusion protein consisting of basic FGF‐PKD‐CBD was found to accelerate osteogenesis in preclinical models for bone fracture and spinal fusion. The presence of the PKD domain may accelerate the wound healing process with less potential for side effects. Our study will help understand the molecular mechanism of the promising drug candidate.Support or Funding InformationSupported by a grant from NIGMS (P20 GM103429) at NIH.Travel funds supported by University of Arkansas Graduate School.
Strategies for Point‐of‐Care Detection of Nucleic Acid Targets
Authors: Broyles David , Deo Sapna K. 
Published: November 2023

In order avoid complex detection platforms that require sophisticated equipment and trained personnel, point‐of‐care assays must incorporate technology that involves minimal user interaction and easily detectable output while maintaining high sensitivity and selectivity. In addition, the ability to provide multiplexed output can increase device utility and save valuable time for healthcare providers. Rather than rely upon miniaturization of current technology, we are attempting to provide low‐cost substitutes for laboratory tests that can provide the end user sufficient information to accurately diagnose and treat diseases and infections without waiting for traditional laboratory testing or having to schedule follow‐up appointments.Support or Funding InformationThis work was supported by grants from the National Science Foundation (CHE‐0748648) and the National Institutes of Health (EB008231‐01). The authors would like to thank the Department of Biochemistry and Molecular Biology at the University of Miami – Miller School of Medicine.