bluuebunny/crossref_metadata_2025 huggingface dataset:
Sodium Caprate Increases Electrogenic Anion Secretion via TRPV4, ATP‐P2Y and VIP‐VPAC1 Pathways in Rat Duodenum
Authors: Akiba Yasutada , Kaunitz Jonathan D.
Published: April 2020

Although luminal short‐chain (SCFA) and long‐chain fatty acids (LCFA) stimulate mucosal protective duodenal bicarbonate secretion (DBS), the role of medium‐chain fatty acids (MCFA) in DBS has not been studied. Thus, we examined the effects of MCFA on DBS in vivo and short‐circuit current (Isc) in the Ussing chamber.

MCFA (C6‐C12, 0.1 – 30 mM) were applied to the mucosal or serosal bath of the Ussing chamber mounted with the muscle‐stripped mucosa‐submucosa preparations of rat proximal duodenum. A duodenal loop was perfused with sodium caprate (C10, 1 mM) in anesthetized rats with total CO2 output measured.

Among MCFA, sodium caprate (C10) dose‐dependently (1 – 30 mM luminally and 0.1 – 3 mM serosally) increased Isc, which was sustained > 10 min after reaching a plateau, whereas other MCFA (C6, C8, and C12) had little effect. The luminal caprate (10 mM)‐induced Isc increase was delayed by luminal addition of ibuprofen (1 mM), a sodium‐dependent monocarboxylate transporter‐1 (SMCT‐1) inhibitor. In contrast, serosal caprate (1 mM)‐induced Isc increase was partially inhibited by serosally applied ruthenium red (0.1 mM), the selective TRPV4 antagonist HC067047 (0.1 mM), suramin (0.5 mM) and abolished by the VPAC1 antagonist PG97‐269 (1 μM), whereas capsaicin pretreatment (10 μM), the selective TRPA1 antagonist HC030031 (0.1 mM), atropine (10 μM), or selective 5‐HT3 or 5‐HT4 receptor antagonists had no effect. The selective TRPV4 agonist GSK1016790 (10 μM) increased Isc, whereas the selective MCFA receptor GPR84 agonist ZQ16 had little effect on Isc. Luminal perfusion of caprate increased the rate of DBS in vivo.

These results suggest that luminal caprate is absorbed via SMCT1, followed by stimulation of DBS via the TRPV4‐ATP/P2Y‐VIP/VPAC1 pathways in rat duodenum. This provides a new therapeutic pathway to enhance duodenal mucosal defenses.

Support or Funding Information

VA Merit Review and Shire Pharmaceuticals
Evaluating Chlorophyll and Nitrogen Production in Edible Plant Sources Grown Under 5 Gigahertz Radiofrequency Radiation Emissions
Authors: Tabor Aaron J. , Greyeyes Shawna , Wilson Kobe
Published: April 2020

By 2022 the demand for constant connectivity to high speed wireless communication networks is predicted to skyrocket with over 12 billion mobile devices and almost half a billion public Wi‐Fi hot spots. Both 5th generation (5G) cellular networks and current IEEE 802.11 Wi‐Fi can transmit radiofrequencies in the 5 Giga Hertz (5 GHz) range. Higher frequencies, such as those in the 5 GHz range, have been shown to be more harmful to humans and biological systems than lower frequencies. Although not well understood, frequencies generated in this range by newly established 5G cellular networks, and common Wi‐Fi 5 GHz networks, may pose a danger to biological systems which could have a significant impact on human health.

This work looks to examine the effects of 5 GHz radiofrequency radiation on chlorophyll production and nitrogen levels in green leafy plants, in particular spinach. Chlorophyll is the most important intermediate in the conversion of light to organic matter in photosynthesis. Nitrogen is known to be directly proportional to chlorophyll content and is found in high amounts within enzymes, proteins, and thylakoid membranes required for photosynthesis. Spinach is known to have high levels of chlorophyll and has been chosen as the plant for testing. Using a TYS‐B Portable Chlorophyll Meter, chlorophyll and nitrogen levels will be non‐destructively measured over 5 weeks of growth under close bombardment from 5 GHz generated radio emissions in treatment groups and control groups shielded from all radio frequency emissions.

If statistical significance suggests chlorophyll and nitrogen levels are decreased between treatment and control groups, further investigation may be warranted to assess the impact on human and plant health. Lower chlorophyll levels could decrease overall group weight and may contribute to a decline in pollinators. Decreased pollinators and lower crop yields could cost consumers billions of dollars in lower availability. As high frequency radio emissions continue to increase across the globe, any information would be available in determining possible dangers from these new technologies.

Support or Funding Information

• Bridges to Baccalaureate Grant awarded through National Institute of General Medical Sciences, Coconino Community College NIH Grant # 1R25GM102788‐01
Effects of amino acid composition on the requirements for J‐proteins by artificial prions
Authors: Miller Sarah C. , Hayward Rachel E. , Cole Sierra J. , Singh Atul K.
Published: April 2020

Yeast prions are non‐Mendelian transmissible agents that are able to induce abnormal folding of specific proteins. The composition of yeast prions is usually in‐register, cross‐beta amyloid structures. Prion‐forming proteins have domains with unusual amino acid content that is typically rich in glutamine and/or asparagine. The chaperone protein network in yeast regulates the correct folding of proteins and is inexorably linked to the spreading of prions to daughter cells during division through a process called fragmentation. Specifically, the core “prion fragmentation machinery” at least minimally includes the proteins Hsp104, Hsp70 and one Hsp40, also known as a J‐protein. The relationship between the amino acid content of the prion‐forming domain (PrD) and chaperone proteins required for fragmentation, if any, is still unclear. Here we explored a system of engineered prions that resemble the Sup35 protein of S. cerevisiae, with single heterologous amino acids interspersed between polyQ sequences every fifth residue in the PrD of the construct. This domain determines the likelihood of a protein to form aggregates in vivo, and so by controlling the amino acid content in this region we can study the impact of specific amino acids and their interactions with chaperone proteins in the propagation of yeast prions. Specifically, requirements for the Hsp40 Sis1 is being investigated using multiple approaches, including plasmid‐shuffling experiments and repression of Sis1 levels using tetracycline. Strains have also been developed to test for requirements for additional J‐proteins for prion propagation. Overall, the long‐term goal for this research is to gain a deeper understanding of the relationship between amino acid content and chaperone protein interactions in prion propagation.

Support or Funding Information

This work was supported by the Lafayette College Chemistry Department, the EXCEL research scholarship program (
www.lafayette.edu), the National Institute of General Medical Sciences of the National Institutes of Health under Award Number R15GM110606, and the Henry Dreyfus Teacher Scholar Award. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or the Dreyfus Foundation.
A comparative analysis between PrPSc and α‐synuclein to explore the structure‐function relationships of pathogenic protein misfolding in prion diseases and Parkinson’s disease
Authors: Peterson Alison , Abdulwali Ahlaam , Bunday Priscilla , Fiedor Lauren , Lee Seyoung , Merlin Daniela Hernandez , Morgan Elizabeth , Torelli Julianna , Yeoh Ming Ying
Published: April 2020

Prion diseases, or transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative diseases affecting humans and other mammals, caused when the alpha‐helix rich prion protein (PrPC) misfolds and converts into a beta‐sheet rich insoluble conformer (PrPSc), which aggregates into toxic amyloid structures. The toxic protein misfolding spreads through a “prion‐only” mechanism in which the diseased PrPSc promotes the misfolding of PrPC. Parkinson’s disease is a neurodegenerative disease characterized by intraneuronal misfolded‐protein aggregates (Lewy bodies and Lewy neurites). Recent research suggests that α‐synuclein may contribute to the pathology of Parkinson’s disease in a prion‐like fashion when a misfolded version of α‐synuclein acts as a template for the misfolding of healthy α‐synuclein, resulting in pathological aggregation. Both prion diseases and Parkinson’s disease cannot be cured and are ultimately fatal. Further exploring the structure‐function relationships in these proteins and how they drive the pathologies of prion diseases and Parkinson’s disease will better our understanding of these diseases. The Minnetonka MSOE Center for BioMolecular Modeling SMART Team used 3D modeling and printing technology to examine the structural similarities and differences of α‐synuclein and the prion protein to further elucidate the mechanisms of pathological protein misfolding.
A Study on Reduction of Occupational Stress of the Hi‐Tech Employees by Schumann Resonances
Authors: Lee Peiying , Hung Jiayi
Published: April 2020

This study is expected to explore the impact of Schumann resonances on the work stress of high‐tech industry practitioners. Schumann wave, or Schumann resonance, is described as “the heartbeat of the earth”. It is a low‐frequency wave (7.83 Hz) that can penetrate any substance. If the human body is often stimulated by Schumann waves, it can receive a larger amount of natural energy to let natural spirit more healthy. The high‐tech industry has always been the focus of Taiwan’s economic growth. Most of the employees engaged in high‐tech industries face enormous work pressures, which in turn affect work efficiency and personal quality of life. In recent years, natural therapy and cranial neurology often explore the relationship between cranial nerve cells and Schumann wave. Therefore, the purpose of this study is to understand whether the use of Schumann wave can alleviate the work pressure of high‐tech industry employees.

This study is divided into two parts: one is the use of heart rhythm analysis, brain wave instrument, gas field camera to analyze the effect of the Schumann wave; the second is to analyze the high‐tech industry employees after using Schumann wave, under work pressure Whether to achieve the phenomenon of mitigation; finally explore the current situation of the work pressure of high‐tech industry employees, how the industry should respond to human resources management. It is hoped that the results of this research will provide high‐tech industry employees with solutions to work control and workload, to adjust their work pressure, to reduce the imbalance of work and life of such employees, and to enhance the personal life of the work. Positive benefits.

Support or Funding Information

Funding of this study is supported by Tzu Chi University of Science and Technology and the PI Semiconductor Corp., Taiwan.
Hippo pathway interacts with Wnt pathway to regulate the neural crest cells
Authors: Wang Jun
Published: April 2020

The neural crest (NC) cells are migratory multipotent cells during embryogenesis, which differentiate into various derivatives and contribute significantly to tissues and organs. The Hippo pathway is a conserved anti‐growth fundamental pathway, yet its role in NC remains poorly understood. We found that Hippo pathway plays pivotal roles in NC cells proliferation, migration and differentiation, based on data obtained from comprehensive studies using in vivo NC conditional knock‐out mouse models and in vitro NC cells. Deficiency of Hippo effectors Yap and Taz caused defects in NC‐derived structures in mice such as vascular and cranial bone defects, as well as failure of NC cells to proliferate, migrate and differentiate. Notably, our motif analysis of ATAC‐seq (assay for transposase‐accessible chromatin with high‐throughput sequencing) data in mouse craniofacial tissues and human NC cells indicated that genome‐wide, 38.9% genes have enriched Tead (Yap/Taz cofactor) motifs are also enriched in Tcf/Lef (β‐catenin cofactors) motifs, suggesting that Hippo interacts with Wnt to coordinately regulate gene expression in NC cells. Wnt‐β‐catenin pathway, another fundamental pathway, has been shown to play a key role in NC cells. Our co‐IP data uncovered a direct interaction between Yap/Taz and β‐catenin in NC cells. Furthermore, our RNA‐seq data in mouse craniofacial tissues and Reverse Phase Protein Array (RPPA) data in mouse NC cells indicated that many known Wnt target genes important for cell migration and fate determination were also regulated by Yap/Taz. In addition, Yap/Taz‐Tead and Tcf/Lef‐β‐catenin complexes coordinately and directly regulate the expression of these genes. Together, our findings uncover novel roles of hippo‐Yap pathway in regulating NC cells, which partially functions through interaction with Wnt‐β‐catenin pathway.

Support or Funding Information

This work was supported by grants from the National Institutes of Health (R56HL142704, R03DE025873, K01DE026561 to J.W.).
Pharmacological studies of morphine in a novel humanized mu opioid receptor mouse model
Authors: Huang Yi-Han , Yeh Shiu-Hwa , Loh Horace H. , Chuang Jian-Yin
Published: April 2020

Full‐length 7‐transmembrane (TM) variants of mu opioid receptor (MOR) share similar amino acid sequences of TM domains in rodents and humans; however, interspecies differences in N‐ and C‐terminal amino acid sequences of MOR splice variants dramatically affect the downstream signaling. Thus, it is essential to develop a mouse model that expresses human MOR for opioid pharmacological studies. We generated two lines of fully humanized MOR mice, line #1 and #2. The novel murine model having human OPRM1 genes and human‐specific variants was examined by RT‐PCR. Humanized MOR mice were characterized in vivo using a tail‐flick, charcoal meal, open field, tail suspension, naloxone precipitation tests, and rectal temperature measurement. The data indicated that wild‐type (WT) and humanized MOR mice exhibited different pharmacology of morphine, including antinociception, tolerance, sedation, and withdrawal syndromes, suggesting the presence of species difference between mouse and human MORs. Therefore, humanized MOR mice could serve as a novel mouse model for pharmacogenetic studies of opioids.
PHYTOCHEMICAL COMPOSITION, ANTI‐INFLAMMATORY AND ANTI‐MICROBIAL ACTIVITIES OF SOME SELECTED SEAWEED IN EASTERN CAPE, SOUTH AFRICA
Authors: Oyedeji Adebola Omowunmi , Saibu Gbemisola Morounke , Nakin Motebang Dominic , Oyedeji Opeoluwa , Meyer Mervin
Published: April 2020

Introduction

Sea algae are widely consumed in the worldwide especially in South Africa. Most of these plants contain some phytochemicals with various potential biological activities. The present study investigated the presence of phytochemical constituents, and anti‐microbial and anti‐inflammatory potentials of methanol extracts of Eklonia radiate(ER) and Jania verucosa (JV).

Materials and Methods

Marine macro‐algae were collected from two different rocky shores areas in East coast (Mbashe and Port St John rivers), Mthatha in South Africa during low tides. The collected marine macro‐algae were rinsed with distilled water and dried at room temperature (25°C). The samples were grinded and extracted with methanol. Qualitative phytochemical analysis for alkaloids, cardiac glycosides, flavonoids, glycosides, phenols, resins, saponins, steroids, tannins and terpenoids were done by following standard procedures. Anti‐microbial assay were performed against six different bacterial pathogens, while In vitro anti‐inflammatory activities of both extract were evaluated using albumin denaturation assay. Diclofenac was used as a standard drug for the anti‐inflammatory activity.

Results

Phytochemical screening revealed the presence of tannins, saponins, flavonoids, steroids, alkaloids, reducing sugars and terpenoids and polyphenols in both extracts. The average minimum inhibitory concentration (MIC) values of the plants extracts ranged from 0.156–5.0mg/ml after 24 h of incubation. Methanol extract of Jania verucosa had the most significant biological activity with the least MIC values of (0.16 mg/ml),while the anti‐microbial activities of methanol extracts of JE and ER gave different zones of inhibition on the five (E.coli, K. Pnemonia, MRSA, P.aureginosa and S.epidemidis) pathogens while there was no growth inhibition on S.pyogene isolates tested on both extracts. The results showed that ER and JV extracts at a concentration range of 0.312‐ 0.02mg/ml significantly (p<0.05) protects the heat induced protein denaturation.

Discussion and Conclusion

From the result, it can be concluded that the presence of phytochemicals present in the extracts could be responsible for the anti‐microbial activity. Further work should be done to isolate the bioactive compound (s) and biological activities of these seaweed.
Chronic Sustained Hypoxic Exposure Can Improve Glucose Metabolism in Mice
Authors: Park Yeram , Hwang Deunsol , Kim Jisu , Lim Kiwon
Published: April 2020

Purpose

Hypoxic therapy has been reported to improve glucose metabolism. In previous studies, there were many studies that determined whether hypoxia regulate glucose metabolism. However, it is still unclear whether hypoxia would only affect whole‐body energy expenditure and energy utilization. In addition, along with energy metabolism, it needs to confirm the gene expression associated with glucose metabolism. Therefore, the purpose of the present study was to investigate the effects of hypoxia exposure on resting metabolic rate, changes of protein expression related to glucose metabolism and mitochondrial biogenesis in muscle tissue.

Methods

Seven‐week‐old ICR male mice (n=16) were divided into two groups: normoxia pair‐fed to hypoxia (Nor), chronic hypoxia (Chr). Normoxia group was exposed to 21% O2 and chronic hypoxia group was 12% O2 for 3 weeks. After 3 weeks, we confirmed resting metabolic rate (RMR), body composition, and protein expression related to glucose metabolism for hexokinase 2 (HXK2), pyruvate dehydrogenase (PDH) and mitochondrial biogenesis for peroxisome proliferator‐activated receptor gamma coactivator‐1 alpha (PGC‐1α). RMR was measured using an open circuit calorimetry system.

Results

In resting metabolic rate, carbohydrate oxidation and energy expenditure were significantly higher in the Chr group than in the Nor group. In soleus muscle, PDH protein level was higher in the Chr group than Nor (p=0.015) group. HXK 2 protein level tended to be higher about 21% in the Chr group (p=0.09). PGC1α protein level was higher in the Chr group than Nor group (p=0.032).

Conclusion

Our data shows that chronic sustained hypoxia significantly improved energy metabolism. Especially, carbohydrate oxidation and protein levels related to glucose metabolism and mitochondrial biogenesis were higher than normoxia group. These observations suggest that chronic exposure for 3 weeks could serve as an effective therapy for glucose metabolic disorder. In the future study, it would be necessary to elucidate whether hypoxia exposure could improve glucose metabolism through diabetic mice model.
FUT2 deficiency may influence the pathogenesis of inflammatory bowel diseases through gut microbiome
Authors: Cheng Sijing , Hu Jun , Wu Xianrui , Jiao Na , Li Yichen , Huang Yibo , Zhu Ruixin , Zhi Min , Zhu Lixin , Lan Ping
Published: April 2020

Background & Aims

Non‐functional fucosyltransferase 2 (FUT2) polymorphisms are associated with inflammatory bowel diseases (IBDs). FUT2 is required for the proper production of oligosaccharides and glycoproteins. These free or attached oligosaccharides have a large impact on the gut microbiota. In this study, we investigated the role of the gut microbiota in IBD pathogenesis with FUT2 deficiency.

Method

We recruited 56 Crohn’s disease (CD) and 25 ulcerative colitis (UC) patients with endoscopically confirmed disease from the IBD clinic in 6th Affiliated Hospital of Sun Yat‐sen University in Guangzhou, China between March 2016 and July 2018. Individuals were asked to provided stool and blood samples respectively. To determine the genotypes of the patients at rs1047781 (A418T) and rs601338 (G461A) of the FUT2 gene, blood DNA was extracted and FUT2 coding sequence was sequenced. For microbiome study, fecal DNA was collected and the V5–V6 region of the 16S rDNA was sequenced with a MiSeq platform.

Result

The incidence of wild‐type, heterozygous and homozygous non‐functional mutations of FUT2, were found to be 32% (26), 49% (40) and 18% (15), respectively, in IBD patients. Significant structural and functional difference were observed at every taxonomic levels among these three groups. Interestingly, the abundance of butyrate producing Dorea, Coprococcus and Ruminococcus was significantly higher in the group carrying homozygous non‐functional FUT2 than those of the other groups (wild‐type and heterozygous non‐functional FUT2, P<0.05). The PICRUSt functional analysis based on the 16S data showed that several carbohydrate synthesis pathways including UDP‐2,3‐diacetamido‐2,3‐dideoxy‐α‐D‐mannuronate biosynthesis and sucrose biosynthesis pathways were enriched in IBD patients with homozygous non‐functional mutation of FUT2 (P<0.05).

Discussion

Our results indicated that FUT2 non‐functional mutation was associated with elevated butyrate producing microbiota, which is in concert with elevated gut microbial capacity for carbohydrate production. FUT2 homozygous mutations may lead to the compensatory increase of carbohydrate production, providing fermentation substrate for the production of short‐chain fatty acids by intestinal flora. Our results may provide a theoretical basis for IBD treatment based on microbiome intervention.

Support or Funding Information

1.National Natural Science Foundation of China 81774152, 31200986, 41530105, 81770571,81970452. 2.Guangzhou laboratory clinical innovation project 2018GZR0201005. 3.National Postdoctoral Program for Innovative Talents of China BX20190393. 4.Natural Science Foundation of Shanghai 16ZR1449800. 5.the University at Buffalo Community of Excellence in Genome, Environment and Microbiome (GEM).
A Rank‐based Longitudinal Correction for Student Self‐selection When Quantifying the Effects of a Voluntary Study Reinforcement Intervention on Exam Performance
Authors: Witchel Harry J.
Published: April 2020

The quantitative effects of voluntary online study interventions are difficult to ascribe causality to because student self‐selection can confound the analysis. An ideal solution would employ counterfactuals to link the intervention to the effect.

OBJECTIVE

To determine whether engaging with an online self‐testing platform improved examination performance.

METHOD

Institution ethical approval was received as was informed consent. A cohort of first‐year undergraduate medical students were provided with a basic online self‐test opportunity on a voluntary basis. Detailed engagement statistics were provided by the online platform, and these were compared to exam performance data over the year for exams and other assessments that normally are produced. As the same students participated in three modules, whereas only one module had the learning intervention, student’s ranks on each final examination were compared in consideration with the engagement with the learning intervention. An anonymized feedback form regarding the self‐test platform was also incorporated.

RESULTS

Fifty of 158 students in the cohort chose to take part and use the platform. Student feedback suggested that the self‐test platform was well liked (4.06 ± 0.10 /5) and helped them learn more (4.10 ± 0.10 /5). Students who used the platform had a trend for scoring higher on the final examination than those who did not (Cohen’s d = 0.25, unpaired t test, P < 0.10); however, there was no direct correlation between use of the intervention and examination score for the relevant module (beta = −0.0054, R‐squared = 0.029). Furthermore, in the longitudinal analysis, the comparative improvement in examination score rank for students who used the intervention (when compared to their ranks when the intervention was not available) was minimal (beta = 0.73 rank increase per 100 questions practiced, R‐squared = 0.0098).

CONCLUSIONS

Improved cross‐sectional performance of those students who chose to participate in the intervention is likely due to self‐selection of engaged students. The lack of clear benefits of this learning intervention when analyzed longitudinally may be due to the intervention’s focus on a small part of the curriculum that was poorly represented on the exam as well as to other known limitations in the intervention.
Protective Role of P62/SQSTM1 on Acute Ischemia‐Induced Arrhythmia Susceptibility
Authors: Hwang Hyun Seok , Rodriguez Jose , Koh Yeojung , Parvatiyar Michelle S. , Salazar Gloria
Published: April 2020

Introduction

Cardiac ischemia diminishes the intracellular defenses of myocardial cells, resulting in contractile dysfunction, and often leads to ventricular arrhythmias. Recently, we have reported that autophagy adapter protein, p62, modulates the oxidant‐induced cellular Ca handling in myocytes isolated from a mouse with chronic ischemia. Here we investigated the effect of p62 suppression on ventricular arrhythmias after acute ischemia injury in intact heart preparations.

Methods

Isolated hearts from wild‐type (WT), heterozygote p62 (HET), and homozygote p62 (HOM) mice (n=6–8 per group, both sexes at 10–12 weeks of age) were prepared for global ischemia (15 min steady‐state, 30 min ischemia, and 60 min reperfusion) with electrocardiogram recording. At the end of the experiment, hearts were harvested for biochemical analysis.

Results

The steady‐state heart rates (HR) were not different among groups. The HR during the reperfusion tended to decrease in HOM hearts (HR, bpm; WT, 322±36, HET, 302±33, HOM, 249±20). The level of p62 protein expression decreased up to 60% in HET hearts compared to WT hearts. The frequency of ventricular arrhythmias reduced in the HET hearts, and further decreased in the HOM hearts during 60 min of reperfusion (Premature ventricular contraction, PVC/min; WT, 2.71±1.16, HET, 0.61±0.18, HOM 0.26±0.10*, * <0.05 vs. WT). The suppression of the p62 gene has a protective effect on acute ischemia‐induced ventricular arrhythmias in intact hearts.

Discussion

Our results suggest that p62 protein may directly contribute to ventricular arrhythmogenesis via intrinsic beta‐adrenergic signaling in the intact heart after acute ischemia.

Support or Funding Information

Research Support: Florida State University
pH‐responsive nanoparticles for Pt (II) delivery to ovarian cancer cells.
Authors: Mieszawska Aneta Joanna , Wlodarczyk Marek T. , Dragulska Sylwia A. , Poursharifi Mina , Chen Ying , Martignetti John A.
Published: April 2020

Platinum‐based agents represent the most widely used chemotherapy against cancer cells. The effectiveness of Pt (II) treatment depends upon two major factors: 1) cellular accumulation and 2) cellular recognition of the platinum‐induced damage leading to cancer cell apoptosis. Limitations of Pt (II) therapy include inappropriate drug activation in the blood compartment and interaction of Pt (II) agents with plasma proteins. Together these factors result in systemic toxicity, decreased targeted cancer cell delivery, and ultimately, leads to treatment failure. To overcome these major limitations, our work has focused on the synthesis of lipid/polymer nanoparticles (NPs) encapsulating Pt (II) therapy. The NP’s core consists of Pt (II) modified poly(lactic‐co‐glycolic) acid (PLGA‐Pt) polymer. The drug payload within PLGA‐Pt NPs is 5 wt. %, and the NPs are 180 nm in diameter with low polydispersity of 0.115. We explore DNA aptamers as active targeting ligands, which are a part of the NP’s coating. The pH‐responsive polyethylene glycol (PEG) masks the targeting ligands at physiological pH but exposes them at tumoral pH conditions. Proof‐of‐priniciple studies in ovarian cancer (OvCa) models demonstrate enhanced internalization of the PLGA‐Pt NPs when targeting surface ligands. The NPs are highly efficacious in vitro, lowering OvCa cell viability better than the clinical Pt (II) analog, and reveal tumor targeting in vivo in an OvCa mouse model. Taken together our results demonstrate a novel method of delivering Pt‐based drugs, which can overcome current clinically‐relevant limitations.

Support or Funding Information

NIH/NCI1R01CA238539‐01
Histamine may directly contract urinary bladder smooth muscle
Authors: Jones B. Malique , Vega Rodríguez Osvaldo J. , Mingin Gerald C. , Tykocki Nathan R.
Published: April 2020

Mast cell degranulation and histamine release contribute to painful bladder syndrome, urinary tract infections, interstitial cystitis and other bladder disorders. The effects of histamine are well‐studied in other tissues, but little is known about the role of histamine and histamine receptors within the bladder. Since other smooth muscle cells express H1 (contractile) and H2 (relaxant) histamine receptors, we tested the hypothesis that histamine causes contraction of the urinary bladder smooth muscle in mice. All procedures followed institutional guidelines and were approved by the Institutional Animal Care and Use Committees of Michigan State University. Six to 12‐week‐old C57Bl/6 mice were euthanized and dissected bladders were cut into approximately 2 mm wide bladder strips, with or without the urothelium attached, for isometric contractility experiments. Both histamine H1 and H2 receptors were expressed in bladder smooth muscle cells. Increasing concentrations of histamine (100 nM – 300 μM) did not contract strips without urothelium and minimally contracted bladder strips with urothelium. However, bolus administration of 200 μM histamine caused a rapid but transient contraction in strips with and without urothelium. The H1 receptor blocker fexofenadine (5 – 10 μM) blocked these contractions (P<0.05; N=5), whereas the H2 receptor blocker cimetidine (5 – 10 μM) had no effect. In addition, transient receptor potential vanilloid 1 (TRPV1) channel blocker capsazepine significantly reduced histamine‐induced contractions only in bladder strips without urothelium, whereas the Na+ channel blocker tetrodotoxin (TTX) had no effect in any tissue (P < 0.05; N= 3–5). The mast cell activator compound 48/80 (10 μg/ml) contracted urinary bladder smooth muscle, and this contraction was also unaffected by TTX. These results indicate that H1 receptors on urinary bladder smooth cells likely modulate histamine‐induced bladder contraction, and sufficient amounts of histamine can be released from mast cells to cause a contraction.

Support or Funding Information

This research is supported by NIH K01‐DK103840 (NRT) and NIH R01‐DK119615 (NRT & GCM).
The effects of kynurenine metabolites on skeletal muscle in vivo and in vitro
Authors: Kaiser Helen , Ding Ke-Hong , Isales Carlos , Hamrick Mark
Published: April 2020

The cellular and molecular mechanisms underlying loss of muscle mass and strength with age (sarcopenia) are not well‐understood. Kynurenine (KYN) is a circulating tryptophan metabolite that is generated by the enzyme Indoleamine, 2, 3 dioxygenase (IDO), is known to increase with age, and is implicated in several age‐related pathologies. We have previously shown that an increase in KYN in young mice increased oxidative stress and decreased skeletal muscle mass, whereas inhibition of KYN using a small‐molecule inhibitor of IDO 1‐methyl‐D‐tryptophan (1MT) protected mice against the loss of muscle mass and strength with age. There are, however, a number of downstream metabolites of kynurenine, and it is not entirely clear whether the effects of kynurenine are direct or via these various metabolites. To further elucidate the mechanism by which KYN affects skeletal muscle we treated 22 month old male C57Bl/6 mice with two established metabolites of kynurenine; quinolinic acid (qa) and picolinic acid (pa). Qa was fed 1ppm for 8 weeks, and pa was fed 700ppm for 8 weeks. We then measured quadriceps femoris fiber size, weight, and muscle‐specific hydrogen peroxide levels at the end of the treatment period. In vivo QA and PA did not change skeletal muscle size, weight, or oxidative stress levels. We then pursued in vitro studies to evaluate other KYN metabolites that might contribute to muscle loss with aging. We treated C2C12 myoblasts with 10um of KYN, kynurenic acid, anthranillic acid, cinnabarinic acid, quinolinic acid, picolinic acid, nicotinic acid, and nicotinamide, and measured cell death and hydrogen peroxide levels. Cell death was increased by 10% in all groups compared to control (ANOVA P<.0001). Hydrogen peroxide was increased 2 fold in all groups compared to control (ANOVA P<.05). Cinnabarinic acid increased cell death by 25%, and increased hydrogen peroxide by 2.5 fold. These results suggest that some metabolites may be more potent than others, and these metabolites may be involved in age‐related muscle loss. Furthermore, the data suggest that enzymes downstream of IDO may be potential therapeutic targets for the prevention of sarcopenia and possibly other age‐associated conditions associated with KYN accumulation such as bone loss and neurodegeneration.

Support or Funding Information

NIA P01 AG036675
GSK3 Activity is Decreased in The Hippocampus of Male Mice Supplemented with Low‐Dose Lithium in Drinking Water
Authors: Fenech Rachel K. , Ryan Chantal R. , Roy Brian , Fajardo Val A. , MacPherson Rebecca E. K.
Published: April 2020

Sporadic Alzheimer’s disease (AD) is a neurodegenerative disease characterized by neurofibrillary tangles composed of hyperphosphorylated tau proteins and amyloid‐beta (Aβ) plaques. Together, these two histopathological detriments in the brain lead to progressive cognitive decline. Glycogen synthase kinase‐3 β (GSK3β), a kinase found abundantly in the brain, has been implicated in the development of these AD pathologies. GSK3β remains constituently active until phosphorylated at its inhibitory Ser9 residue. When active, GSK3β is capable of inducing tau hyperphosphorylation and can phosphorylate amyloid‐precursor protein (APP), influencing greater levels of Aβ peptide production. Lithium (Li), a GSK3β inhibitor, has been suggested as an AD prophylaxis. However, Li has also been associated with several dose‐dependent adverse side effects. The purpose of this study was thus to examine the effects of a prophylactic low‐dose Li supplementation on brain GSK3β signaling and activity. C57BL/6J male mice were given 10mg/kg/day Li or no Li in their drinking water for 6 weeks (n=12/group) and the prefrontal cortex (PFC) and hippocampal (HIP) tissues were collected for GSK3 activity assay and western blot analyses. Li mice had increased serum Li concentrations (p<0.0001) and decreased hippocampal GSK3 activity (p=0.06) as compared to control mice. pAkt Thr308 phosphorylation, a kinase immediately upstream of GSK3β capable of inducing inhibitory pGSK3β Ser9 phosphorylation, was increased in the PFC of Li mice compared to control mice (p<0.05). However, no differences in pGSK3β Ser9 or Tyr216, an activating residue, were observed between control and Li mice in both the PFC and HIP. Changes in GSK3 activity without changes in inhibitory Ser9 phosphorylation may suggest that a longer supplementation is needed to affect significant changes in the brain. Furthermore, these results demonstrate that the phosphorylation status of GSK3β may not always be a direct translation of its activity. This highlights the importance of measuring GSK3β activity alongside of measures of upstream kinases (i.e. PI3K/Akt signaling) and downstream targets to obtain a better indication of GSK3β’s overall activity within the brain. Overall, this initial work provides evidence that Li can inhibit hippocampal GSK3 activity and alter the phosphorylation status of upstream kinases at a low‐dose. Future work will examine Li’s potential prophylactic effects in a diseased model which better mimics AD (i.e. aged and metabolically‐distressed mice). This is important to further elucidate the efficacy of low‐dose Li in the prevention of AD pathologies.

Support or Funding Information

This work is supported by the Alzheimer Society of Brant, Haldimand Norfolk, Hamilton Halton and NSERC.
The Impact of Acute Hot or Cold Water Immersion on Post‐Exercise Blood Pressure Regulation
Authors: Ely Brett Romano , Robinson Victoria A. , Havens Christopher W.
Published: April 2020

Acute exercise, heat exposure, and cold exposure independently produce short‐term changes in blood pressure (BP). It is currently unknown whether post‐exercise hot water immersion (HWI) or cold water immersion (CWI) impact the magnitude or timeline of changes in BP observed following exercise. The objective of this study was to examine the impact of post‐exercise HWI and CWI on systolic (SBP), diastolic (DBP), and mean arterial pressure (MAP). Ten healthy (6M, 4F; BMI: 23.7±1.7; BP: 125±3/73±3 mmHg) individuals took part in 3 randomized, counterbalanced trials consisting of evening interval exercise (~7k treadmill walking and running with 8×400m high‐intensity intervals) followed by a 30 minute treatment of HWI (immersed to chest in 39–40°C tub), CWI (immersed to chest in 14–15°C tub) or time control (CON; seated passive recovery at room temperature). Brachial BP was measured in triplicate in a seated position pre‐exercise (Pre‐Ex), immediately post‐exercise (Post‐Ex), immediately post‐treatment (Post‐Tx), and following 12h overnight recovery (12h post). Results were analyzed using a 2‐way repeated measures ANOVA. Significant time by treatment interactions were observed for DBP (p=0.0070) and MAP (p=0.0059). Pre‐Ex and Post‐Ex, no differences were observed between groups. Post‐Tx, CWI resulted in increased DBP (+12 ± 3 mmHg; p<0.0001) and MAP (+9 ± 2 mmHg; p=0.0002) compared with Pre‐Ex, while DBP and MAP remained steady in HWI and CON. 12‐hr post‐exercise, both MAP (−6 ± 2mmHg; p=0.0431) and DBP (−7 ± 2mmHg; p=0.0159) were lower than Pre‐Ex in HWI, and no differences were seen in CWI or CON. These data indicate that post‐exercise CWI temporarily increases DBP and MAP, but does not affect blood pressure 12‐h post‐exercise. In contrast, post‐exercise HWI leads to prolonged reductions in DBP and MAP in healthy individuals. Those engaging in exercise to control or reduce blood pressure may experience a greater benefit with the addition of post‐exercise HWI. Future research should examine whether this effect is similarly observed in hypertensive individuals, as first‐morning blood pressure is an important indicator of disease severity and progression.
The Role of Xanthine Dehydrogenase (XDH) and Uric Acid in the Kidney Development and Renal Injury
Authors: Dissanayake Lashodya Vindana , Spires Denisha R. , Levchenko Vladislav , Khedr Sherif , Palygin Oleg , Staruschenko Alexander
Published: April 2020

Uric acid is the end product of purine catabolism in humans and is capable of acting as both an antioxidant scavenging reactive oxygen species and conditionally a pro‐oxidant. Pathophysiological changes in serum uric acid levels (hyperuricemia and hypouricemia) are associated with prevalent diseases, including hypertension and chronic kidney disease as well as rare disorders, such as hereditary xanthinuria. Despite the clear association between uric acid dysregulation and pathology, the mechanisms involved remain unclear. XDH and xanthine oxidase (XO) (together known as Xanthine oxidoreductase (XOR)) is a complex enzyme group that catalyzes the oxidation of hypoxanthine to xanthine and xanthine to uric acid. To assess the role of this pathway beyond purine catabolism, we created a genetic ablation of the Xdh gene in the Dahl salt‐sensitive rat background (SSXdh−/−). Sequencing of SSXdh−/− genomic DNA confirmed a 7‐base‐pair‐deletion in exon 4 of the Xdh gene located on chromosome 6. The absence of Xdh protein expression in homozygotes and a reduction in heterozygotes was confirmed by both Western blot and immunohistochemistry analyses. SSXdh−/− rats exhibited early mortality with 7 out of 28 rats not surviving till 6 weeks of age compared to SSXdh+/− and SSXdh+/+ littermates, all of whom survived. Plasma uric acid of 6 weeks old male rats was 0.25±0.03 mg/dl (N=6) in SSXdh+/+ rats and decreased to a level out of the detectable range by the test in the SSXdh−/− group. The 24hr uric acid excretion was also dramatically decreased in SSXdh−/− rats compared to SSXdh+/+ littermates. Masson’s Trichrome staining revealed severe renal damage with an increase in fibrosis (1 and 14% (N=3 and 2 for male SSXdh+/+ and SSXdh−/−, respectively), and dilated tubules in the SSXdh−/− rats. Total body weight was decreased in SSXdh−/− rats, indicating a failure to thrive compared to control rats (190 ± 4 and 58 ± 8 g; N=6 and 4 for male SSXdh+/+ and SSXdh−/−). Additionally, In SSXdh−/− rats at 6 weeks, Western blot analysis showed a lack of connective tissue growth factor (CTGF), which is known to be critical in the nephrogenesis. No apparent sex‐specific differences in development or kidney injury were identified. Our results suggest that the genetic ablation of Xdh caused uric acid depletion and severe renal damage. Therefore, XOR may be essential for the development of the kidney and survival of the rats by regulating purine catabolism.

Support or Funding Information

Supported by the Department of Veteran Affairs Grant I01 BX004024 and the National Institutes of Health Grants R35 HL‐135749.
CCL2 Mediates Early Renal Leukocyte Infiltration During Salt‐Sensitive Hypertension
Authors: Alsheikh Ammar J. , Dasinger John Henry , Abais-Battad Justine M. , Fehrenbach Daniel J. , Yang Chun , Cowley Allen W. , Mattson David L.
Published: April 2020

Background

Hypertension is reported to be the largest independent risk factor for disease burden globally. Despite the prevalence and burden of hypertension on human health, the mechanisms leading to the development of hypertension in most individuals remain unknown. Both human and animal experimental evidence indicate that immune mechanisms may play a key role in the development of hypertension and associated end‐organ damage. Studies examining mechanisms of Dahl Salt‐Sensitive (SS) hypertension have implicated the infiltration of leukocytes into the kidneys as a key contributor to the hypertension and renal damage. However, the signaling pathways by which leukocytes traffic to the kidneys remain poorly understood.

Aim

The aim of the present set of studies was to use a unique unbiased discovery‐based approach to nominate signaling pathways which was followed by functional testing of the role of the identified pathways in renal leukocyte infiltration.

Methods and Results

We analyzed a kidney RNA‐seq dataset from SS rats fed either a Low Salt (LS‐0.4% NaCl) or a High Salt (HS‐4.0% NaCl) diet. From this analysis, the chemokine (C‐C motif) ligand 2 (CCL2) and receptor CCR2 were nominated as a potential pathway modifying renal leukocyte infiltration. The functional role of the CCL2/CCR2 pathway was tested by daily administration of CCR2 antagonist (RS102895 at 5mg/kg/day in DMSO) or DMSO Vehicle for 3 days (n=13–15/group) or 21 days (n=9–11/group) by intraperitoneal injections to male SS rats during the HS challenge. A variety of parameters were measured throughout the study including blood pressure (measured continuously using radio‐telemetry), circulating leukocytes and renal leukocyte infiltration (by flow cytometry) and renal damage (assessed histologically and using urinary injury markers), body weight, food intake and electrolyte excretion. Results demonstrate that RS201895 treatment, compared to vehicle‐treated rats ameliorated renal damage (urinary albumin excretion; 43.4±5.1 vs 114.7±15.2 mg/day, P<001) and hypertension (144.3±2.2 vs 158.9±4.8 mmHg, P<0.001) after 21 days of HS diet. It was determined that renal leukocyte infiltration was blunted by day 3 of the HS diet (1.4±0.1 vs 1.9±0.2 ×106 CD45+ cells/kidney, P=0.034) in drug‐treated rats. A unique adaptation of an in vitro chemotaxis assay validated the ability of RS102895 to block leukocyte chemotaxis towards CCL2 at in vivo concentrations.

Conclusion/Significance

The results demonstrate that increased CCL2 in SS kidney is important in early recruitment of leukocytes and blockade of this recruitment by administering RS102895, which subsequently ameliorated the renal damage and hypertension. These results provide a unique understanding to an important disease process that has potential therapeutic implications.

Support or Funding Information

Supported by HL137748, HL116264.
Role of Zfra in mitigating epileptic seizure due to WWOX downregulation
Authors: Wen Kuang-Yu , Chang Nan-Shan
Published: April 2020

As a tumor suppressor, WWOX is a recently defined risk factor for Alzheimer’s disease (AD). WWOX limits AD progression due, in part, to its suppression of tau tangle formation by direct binding of tau and tau‐phosphorylating enzymes. Deficiency of WWOX leads to severe neural diseases, including epileptic encephalopathy, microcephaly, intractable seizures and developmental delay, and early death in human and animal newborns. Wwox knockout mice, which survive in less than 1 month, display spontaneous and audiogenic seizures and rapid formation of tau and amyloid aggregates in the brain in less than 3 weeks after birth. During AD progression in humans and mice, pS14‐WWOX is shown to accumulate in the brain hippocampus and cortex. Suppression of pS14‐WWOX by a short synthetic peptide Zfra (zinc finger‐like protein that regulates apoptosis) leads to clear up of tau tangles and amyloid plaques, and restoration of memory loss in triple transgenic mice for AD. Here, we determined that when Wwox wild type and heterozygous mice were pre‐injected with a Zfra4–10 peptide via tail veins, these mice resisted pentylenetetrazone (PTZ)‐induced seizure. Mechanistically, Zfra significantly suppressed pS14‐WWOX in the auditory cortex and hippocampal CA1, CA3, or DG areas. Zfra blocked PTZ‐induced activation of inflammatory microglia and astrocytes in mouse hippocampus. Also, Zfra significantly blocked the expression of RE1‐silencing transcription factor (REST) (>90%), which is a regulator of ion channels and neurotransmitter receptors associated with epilepsy. Together, our observations suggest that Zfra peptide is a potent agent in mitigating epileptic seizure caused by WWOX deficiency.

Support or Funding Information

Ministry of Science and Technology, Taiwan, National Health Research Institute, Taiwan, and Department of Defense, USA.