bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of O‐linked glucose‐fucose disaccharide modification of thrombospondin type I repeats in protein folding and embryo development
Authors: Holdener Bernadette
Published: April 2020

We propose that Protein O‐fucosyltransferase 2 (POFUT2) and β3‐glucosyltransferase (B3GLCT) function to ensure efficient folding of forty‐nine proteins containing tandemly repeated
Thrombospondin
Type 1
Repeats (TSRs). In the endoplasmic reticulum (ER), POFUT2 and B3GLCT recognize properly folded TSRs and act sequentially to add the unusual O‐linked Glucoseβ1‐3Fucose disaccharide to either a serine or threonine residue located within the POFUT2 consensus sequence (C‐X‐X‐S/T‐C). Once all TSRs are modified the target protein exits the ER. In crystal structures the disaccharide forms H‐bonds and van der Waals interactions with underlying amino acids in the TSR, raising the possibility that the disaccharide functions as a surrogate amino acid to stabilize the correctly folded TSR. Results from in vitro folding/refolding assays provide evidence that the disaccharide stabilizes the TSR fold and accelerates the overall rate of protein folding. Consistent with this prediction, loss of POFUT2 or B3GLCT in cell culture impairs trafficking of POFUT2/B3GLCT targets. To begin to evaluate the function of the disaccharide in vivo, we generated mouse loss of function mutations in Pofut2 and B3glct. Loss of Pofut2 causes early embryo lethality due to a block in gastrulation. In contrast, B3glct animals survive, but have craniofacial and skeletal abnormalities, defects in pigmentation, soft tissue syndactyly, and develop hydrocephalus. The mouse B3glct phenotype shares similarities to Peters Plus syndrome in humans, caused by recessive mutations in B3GLCT. The distinct differences in the effects of these mutations during mouse development support a model whereby the O‐linked fucose is essential for folding and secretion of all POFUT2/B3GLCT target proteins and that B3GLCT‐mediated extension to the glucose‐fucose disaccharide is only required by a subset of sensitive targets.

Support or Funding Information

These studies were supported by funding from NIH R01 HD090156 and NIH R01 HD096030 and 2019 Hydrocephalus Association Innovator Award.

Model for how POFUT2/B3GLCT mediated addition of the O‐linked glucose‐fucose disaccharide promotes efficient folding of target proteins containing the Thrombospondin Type 1 Repeats (TSR) fold. Addition of fucose prevents reentry of the TSR to the folding cycle and stabilizes the fold. Extension with glucose provides further stability to the TSR. Once the target protein is fully modified it exits the endoplasmic reticulum (ER).

Figure 1
Pharmacokinetic Prediction of CYP2D6 Genotypes of Metoclopramide in Adults and Children Using Physiologically Based Pharmacokinetic Modeling
Authors: SHIN HYO BIN
Published: April 2020

Metoclopramide (MCP) is a dopamine D2 antagonist and 5‐HT4 receptor agonist to stimulate gastric contractions for the treatment of Gastroparesis and gastroesophageal reflux disease. It is predominantly metabolized in liver by cytochrome P450 2D6 (CYP2D6). Thus, CYP2D6 genetic polymorphism has essential effects on the pharmacokinetics of metoclopramide and exhibits variability between the different phenotypes. Based on our clinical trials, we developed a physiologically based pharmacokinetic (PBPK) model for CYP2D6 *wt/*wt group and scaled to other CYP2D6 genotypes and pediatric group. A 10 mg single oral dose of metoclopramide was given to forty‐three healthy Korean subjects composed of CYP2D6 *wt/*wt (*wt = *1 or *2, n=12), *wt/*10 (n=8), *10/*10 (n=15) and *5/*10 (n=8) genotypes. The plasma concentrations of metoclopramide were measured using an HPLC‐MS/MS system. Based on data of our clinical trials and physicochemical properties, PBPK model of metoclopramide was built utilizing PK‐sim® software (PK‐Sim® 7.4, Bayer AG, Wuppertal, Germany). After that, a PBPK model has fitted the 99.998% confidence interval criteria (Abduljalil K et al., 2014) and validated by comparing it with other clinical trials. We found meaningful differences in AUCinf, AUCend, oral clearance (CL/F) and Cmax in CYP2D6 genotypes (P<0.0001, respectively). The mean Cmax for the clinical pharmacokinetic data were 26.8 ± 9.2, 37.6 ± 6.4, 44.3 ± 9.2 and 45.7 ± 6.9 in CYP2D6*wt/*wt, *wt/*10, *10/*10 and *5/*10 group, respectively. And the mean Cmax for the simulated pharmacokinetic data were 33.9, 42.5, 41.5 and 45.1 in CYP2D6*wt/*wt, *wt/*10, *10/*10 and *5/*10 group, respectively. According to the developed PBPK model of metoclopramide, the observed pharmacokinetic parameters of adults were all within model acceptance criterion, whereas in those of pediatric excluding CL/F met the acceptance criteria. In this study, we first attempted pharmacokinetics prediction of the CYP2D6 genotype of metoclopramide in adults and children using physiologically based pharmacokinetic modeling. This PBPK model could be applied to personalized therapies to determine the appropriate dosage to minimize adverse effects in patients with functionally impaired CYP2D6 activity. So, this PBPK model will help make more effective and less risky clinical decisions in different CYP2D6 genotypes which will lead to a more successful stomach and esophageal problem management.

Observed (circles) and simulated (lines) values of metoclopramide in relation to CYP2D6 genotype in populations. The dashed lines represent the 5th and 95th percentiles of model predicted plasma concentrations.

Figure 1

Individual values for Cmax (A) and AUC0–24hr (B) of metoclopramide in relation to CYP2D6 genotype groups. The horizontal bars are mean values for each genotype group.

Figure 2
Alterations in Copper Homeostasis in Rabbit Model of Atherosclerosis
Authors: Li Hualin , Zhao Lijun , Feng Qipu , Kang Y. James
Published: April 2020

Copper concentrations decrease in atherosclerotic tissues. The present study was undertaken to determine overall alterations in copper homeostasis in the pathogenesis of atherosclerosis. New Zealand white rabbits, aged 10‐weeks‐old, were fed a rodent chow diet containing 1% (w/w) cholesterol or the same diet without cholesterol as control. Twelve weeks after respective diet feeding, the animals were euthanatized by sodium pentobarbital. Rabbits fed cholesterol‐containing diet developed hyperlipemic as defined by a significant increase in the total plasma cholesterol and atherosclerotic lesions in aorta. Copper concentrations in the atherosclerotic tissues were significantly decreased while serum copper concentrations were increased in the hyperlipemic animals in comparison with controls. A detailed analysis revealed that copper concentration in abdominal aorta of the hyperlipemic rabbits was negatively correlated with the severity of the atherosclerotic lesion, stenosis of the lumen area, and collagen deposition. In addition, copper concentrations in the kidney of hyperlipemic rabbits were increased, but in the heart, liver, spleen and lung were decreased. These results suggest that in the pathogenesis of atherosclerosis, changes in copper homeostasis are not only observable in the atherosclerotic tissues, but also in multiple organ systems. These changes would be additive to atherosclerosis as a high risk of cardiovascular disease in humans.

Support or Funding Information

West China Hospital, Sichuan University

(A) The percentage of the aortae staining positively for lipid(Longitudinal of suprarenal abdominal aortae was stained with oil red O). Sections of infrarenal abdominal aortae were stained with EVG for microscopic quantification of lesion areas, (B) the atherosclerotic lesion area and (C) the percent of stenosis of lumen area. Collagen fibers in the lesions were assessed by picrosirius red staining, the percent of Collagen in lesion area. (*P < 0.05)

Figure 1

The concentration of copper in tissues and plasma.

(A) cardiac copper concentration; (B) liver copper concentration; (C) spleen copper concentration; (D) lung copper concentration; (E) kidney copper concentration; (F) duodenum copper concentration; (G) abdominal aortic copper; (H) plasma copper concentration. (*P < 0.05)

Figure 2
Serum Copper Elevation Promotes Hepatic Ceruloplasmin Production and Excretion in Rat Model of Myocardial Infarction
Authors: Yang Dan , Wang Tao , Zhang Jingyao , Kang Y. James
Published: April 2020

Ceruloplasmin (Cp) is a major copper‐binding protein in blood, regulating copper homeostasis. High levels of serum copper and Cp are both risk factors for coronary artery disease, particularly in patients with acute myocardial infarction. However, the relationship between the changes in serum copper and Cp levels in response to myocardial ischemia remains unknown. It is known that myocardial ischemia causes copper efflux from the heart leading to copper elevation in the blood. The present study was undertaken to test the hypothesis that the elevation of serum copper leads to an increase in hepatic Cp production and excretion. Adult male Sprague‐Dawley rats were subjected to left anterior descending (LAD) coronary artery ligation to induce myocardial infarction. Serum copper and Cp levels, as well as changes in hepatic Cp and copper‐transporting P‐type ATPase (ATP7B), were determined from blood and liver samples harvested on day 1, 4, or 7 after the operation. Serum copper concentrations were significantly increased on day 4 after LAD ligation, accompanied by an increase in serum Cp levels and activities. Concomitantly, the protein levels of Cp and copper exporter, ATP7B, were also significantly increased in the liver. Taken together, these results indicate that the elevated serum Cp levels mostly likely result from the increase in Cp production and excretion in the liver in response to the elevated serum copper levels following myocardial ischemia.

Support or Funding Information

West China Hospital, Sichuan University

Changes in hepatic Cp levels. At the time of 1, 4 or 7 day after LAD ligation, the liver tissues were harvested for Western blot and mRNA analysis. (A–C) Changes in hepatic Cp protein levels. (D–E) Changes in the expression of Cp, measured by RT‐PCR. Data are presented as mean ± SD, n=5–6, *P < 0.05. LAD: left anterior descending; MI: myocardial infarction.

Figure 1

Changes in hepatic ATP7B levels. The sample preparation was as the same as presented in Figure 3. (A–C) Western blot analysis was performed to detect the protein level at different time point. (D–E) Changes in the expression of ATP7B, measured by RT‐PCR. Data are presented as mean ± SD, n=4–6, *P < 0.05. MI: myocardial infarction.

Figure 2
The Impact of Teaching Up‐to‐Date Medical Pharmacology Material. Who Wins? The Board Preparation Resources!!
Authors: Hernandez Mark J. , Parker R Wayne , MacGregor Gordon G.
Published: April 2020

Introduction

Pharmacology faculty are faced with the challenge of preparing medical students to become doctors but are also challenged with preparing the students to successfully complete the USMLE Step‐1, and or COMLEX Level‐1 (for osteopathic medical schools). Faculty student evaluations can help highlight the student perspective on this high‐stakes exam and the pressure it brings. But what is a pharmacology faculty to do when traditional resources such as textbooks and even some board preparation resources are not in agreement with the most current therapeutic guidelines.

Methods

Most recently in 2017 and 2018 there were updates in the management of hypertension (2017) and hyperlipidemias (2018), and even the classification of antiarrhythmic drugs (2018). Those updates, amongst others, were most recently addressed in a second‐year cardiovascular system pharmacology course in our institution. Revisions required updating the pharmacology content of the course and sharing the updates on the scope of pharmacology with the physician faculty who also teach about the drugs. We then compared the student feedback in the course from the previous five years using a thematic analysis approach.

Results

The number of times words such as: “clinical”, “integration”, and/or “boards” appeared in course‐evaluation surveys was two to three‐fold higher in 2019 compared to that of previous 5 years. Presenting updated content caused more frustration and discontent among some medical students. When the content did not necessarily match that found in the popular board preparation resources it led to a distrust in the instructor.

Conclusions

The latest pharmacology information may not necessarily support the information found in board preparation resources. In addition, clinical faculty may present therapeutic information based on their own clinical experience. Often it is the case that the pharmacology faculty is solely responsible for the overall content in the curriculum even when it may be presented at different levels from different sources. Students need to succeed on the boards and in our pharmacology courses but what are the faculty to do when the AMSPC knowledge objectives, which have traditionally been used as the standard of what to teach in pharmacology, become outdated. There is a need for updated pharmacology knowledge objectives.

Support or Funding Information

NA

Comparison of the Cardiovascular System End‐of‐Course Evaluations as it pertains to Pharmacology

Figure 1
Waist‐to‐height Ratio as an Indicator to Determinate Obesity and Central Obesity in Pediatric Population
Authors: Mendoza-Hernandez Alma Nubia , Flores-Rojas Lupitha Elizabeth , de Lourdes Silva-Fernandez María
Published: April 2020

Introduction

In school‐age children and adolescents, the obesity is a public health alarm that particularly has been increasing. The highest prevalence rates of childhood obesity have been observed in developed countries; still, its prevalence is increasing in developing countries as well. The best evidence to date suggests that measures of central adiposity should be used in order to best identify individuals at increased risk of obesity‐related ill health. In the clinical environment, techniques such as Body Mass Index (BMI), waist circumference (WC) have been used extensively, but the waist‐to‐height ratio (WHtR) could be a better tool to detect central obesity.

Objective

The objective was to evaluate the association of body mass index (BMI) and waist to height ratio in overweight and obese paediatric age group.

Methods

Is a cross‐sectional study, schoolchildren in a Mexican population, ages from 9 to 18 years. The anthropometric variables measured were waist circumference, body mass index, waist‐to‐height ratio, Waist circumference at the midpoint between the last rib and the iliac crest. The use of The Center for Disease Control and Prevention growth tables classified overweight as at or above 85th percentile and obesity as at or above 95th percentile of BMI. The relationship between waist‐to‐height ratio (WHtR) and body mass index (BMI) was analyzed by X2, t‐test and ANOVA.

Results

A cross‐sectional study of 594 children and adolescents from 9 to 18 years of age. In the analysis the population was grouped by aged group of 9 to 11(23%), 12 to 14 (33%) and 15 to 18 years(44%). The body mass index (BMI) for age showed 18% for overweight and 13% for obesity. The waist to height ratio was 24% for higher cardiometabolic risk with a mean of 0.47 and a waist circumference of 73.9cm. A cardiometabolic risk by WtHR was 4% in normal BMI/age, in overweight 8% and in Obesity was 12% (p=0.01).

Conclusion

The prevalence of overweigh and obesity was 31%. It is important to recognize the capacity of anthropometric measurements on identifying overweight and obesity diagnosis. A combined diet and physical activity intervention conducted in the community with a school component should be applied preventing obesity or overweight. The waist to height ratio was 24% for cardiometabolic risk. Anthropometric measurements such as weight, height and waist circumference are simple and effective as global indicator for health risks.

Support or Funding Information

UPAEP UNIVERSITY

Anthropometric measurements in the paediatric group

AGE (yrs)

Weight (kg)

Height (cm)

Waist circumference (cm)

BMI (kg/m2)

WHtR

Mean

13.6

55.6

158.6

73.9

21.9

0.47

SD

2.34

14.4

11.6

10.3

4.1

0.06

Min

9.0

23.0

127.0

50.0

13.6

0.34

Max

18.0

115.0

195.0

125.0

40.5

0.74

Range

9.0

92.0

68.0

75.0

26.9

0.4

*Standard Deviation

Proportion categorized by WHtR Risk and BMI

Table 2
Analysis of FAM19A2/TAFA‐2 function
Authors: Okada Shuichi , Okada Junichi , Yamada Masanobu
Published: April 2020

FAM19A2/TAFA‐2, a member of the chemokine CC family, shares 31% sequence identity with MIP‐1α, which is known to elevate body temperature and reduce food intake. A single administration of 250 pM of FAM19A2/TAFA‐2 to the third ventricle of mice just before the initiation of dark period increased food intake and meal number significantly, but reduced meal size during the dark period. The respiratory exchange rate and energy expenditure were increased significantly during the dark period, while the ambulatory count and vertical activity were not affected. These data suggest that FAM19A2/TAFA‐2 participates in the regulation of food intake and metabolic activities.

Effect of FAM19A2 on Food intake, Meal number, and Meal size

Figure 1

Effect of FAM19A2 onRER and EE

Figure 2
Platelet extravasation across inflamed venules depends on CD18, mast cells and neutrophils
Authors: Bray Monica A. , De La Cruz Angie , Courson Justin , Magadi Sri , Landry Paul T. , Lam Fong W. , Hanlon Samuel D. , Smith C. Wayne , Burns Alan R. , Rumbaut Rolando E.
Published: April 2020

Platelets and neutrophils are often recruited at sites of microvascular inflammation. While neutrophil extravasation in inflammation is well characterized, platelet extravasation in inflammation is poorly understood and has only been documented in a small number of studies. We showed previously that mice expressing low levels of the leukocyte integrin CD18 (CD18hypo) had reduced total recruitment of platelets (intravascular and extravascular) in the corneal limbus following corneal epithelial wound injury. In this study we sought to determine the role of CD18 in platelet extravasation. Following corneal wound injury, wild‐type (WT) mice had evidence of platelet extravasation across limbal venules; however, CD18hypo mice had markedly reduced platelet extravasation. In view of isolated reports that platelets express CD18, we compared blood platelet counts and ex vivo platelet function under shear stress between CD18hypo and WT mice. Blood platelet counts were measured with a Scil Vet ABC hematology analyzer (Scil animal care company). Flow chamber assays were conducted using a microfluidic BioFlux System (Fluxion Biosciences) with plates coated with type I collagen (25 μg/ml; Helena) and blocked with 5% Bovine serum albumin. The labeled blood was perfused over the collagen‐coated surfaces at two values of fixed shear stress (16 dyne/cm2 and 30 dyne/cm2). Platelet counts and platelet adhesion to collagen at both levels of shear stress were comparable between CD18hypo and WT mice. Since a variety of leukocytes express CD18, including mast cells and neutrophils, we performed experiments to assess the role of these leukocytes in platelet extravasation. We found that CD18hypo mice had a small but statistically significant decrease in mast cell number and a marked decrease in degranulated mast cells as compared to WT mice following wound injury. Further, corneal epithelial wound injury in mice deficient in mast cells (KitW‐sh/W‐sh) resulted in a marked decrease in platelet extravasation as compared to WT mice. Finally, antibody‐induced depletion of circulating neutrophils resulted in a marked decrease in platelet extravasation relative to control mice. Overall, these studies demonstrate that platelet extravasation in a corneal wound injury model of inflammation depends on CD18, mast cells, and neutrophils.

Support or Funding Information

Supported by: NIH EY018239, EY17120, HL079368 and VA BLR&D Merit Review Award I01 BX002551. M.A.B. was supported by NHLBI T32 HL139425

Extravascular platelets (green) are evident surrounding venules 24 hours postwounding in wild type mice.

Figure 1

Platelets from CD18 hypomorphic mice had similar adhesion under shear as those from Wild‐type mice; blood platelet counts were similar in both strains

Figure 2
Explaining the impact of environmental risk factors on cardiovascular health by the “exposome” concept
Authors: Daiber Andreas , Münzel Thomas
Published: April 2020

There is growing evidence that environmental risk factors (pollution and non‐chemical stressors) contribute to the global burden of cardiovascular, metabolic and mental disease. Clinical and epidemiological studies support that traffic‐associated environmental risk factors, air pollution and noise exposure, are associated with a higher risk for cardiovascular disease and significantly contribute to overall mortality. According to the results of the Lancet Commission on pollution and health, up to 9 Mio global annual deaths can be attributed to environmental pollution [Landrigan et al., Lancet 2018]. The numbers will rather increase in the future, because of increasing urbanization and continuous refinement of global exposure‐mortality models, which is supported by the recently reported global all‐cause mortality rate attributable to ambient air pollution by PM2.5 and O3 of 8.79 Mio [Lelieveld et al. and Münzel, Eur Heart J 2019]. Air pollution is obviously the leading health risk factor in the physical environment, followed by water and soil pollution with heavy metals, pesticides, other chemicals and occupational exposures. However, non‐chemical environmental health risk factors such as mental stress, light exposure, climatic changes and traffic noise are so far ignored by global health action plans. Especially for traffic noise‐related health effects there are numerous clinical and epidemiological studies reporting significant impact on cardiovascular disease. In this respect, the “exposome” concept represents a comprehensive description of lifelong exposure history and a rather novel scientific field that is now investigated more systematically. We here provide an in‐depth overview on the health effects of the external exposome, with emphasis on air pollution and traffic noise, and briefly present the actual studies on this topic. In addition, we summarize our previously published experimental research investigating effects of aircraft noise exposure in mice and men providing mechanistic insights on how noise contributes to non‐communicable disease.

Support or Funding Information

The present work was supported by the Boehringer Ingelheim Foundation “Novel and neglected risk factors” (to A.D. and T.M.).

The exposome concept. The external exposome represents the sum of all environmental exposures including behavioral/ lifestyle factors. The external exposome (e.g. mental stress and environmental pollution) confer changes of the internal exposome (e.g. altered circadian clock by forward/backward shift, stress hormones, inflammation and oxidative stress) leading to health risks and disease conditions (e.g. atherosclerosis, vascular stenosis and myocardial infarction). BJP, submitted.

Figure 1
Regulation of vascular function and inflammation via crosstalk of reactive oxygen and nitrogen species from mitochondria or NADPH oxidase
Authors: Daiber Andreas
Published: April 2020

Oxidative stress plays a key role for the development of cardiovascular, metabolic and neurodegenerative disease. This concept has been proven by using the approach of genetic deletion of reactive species producing (pro‐oxidant) enzymes as well as by the overexpression of reactive species detoxifying (antioxidant) enzymes leading to a marked reduction of reactive oxygen and nitrogen species (RONS) and in parallel to an amelioration of the severity of diseases. Vice versa, the development and progression of cardiovascular diseases is aggravated by overexpression of RONS producing enzymes as well as deletion of antioxidant RONS detoxifying enzymes. We have previously identified crosstalk mechanisms between different sources of RONS, which can amplify the oxidative stress signal. Pathways and potential mechanisms leading to this crosstalk will be analysed in detail and highlighted by selected examples from the current literature and own data including hypoxia, angiotensin II‐induced hypertension, nitrate tolerance, aging and others. The general concept of redox‐based activation of RONS sources via “kindling radicals” and enzyme‐specific “redox switches” as well as the interaction with redox‐sensitive inflammatory pathways will be discussed. An outlook will be provided with preliminary data on the existence of such crosstalk in the setting of diabetes but also mouse models of cardiovascular dysfunction triggered by environmental noise exposure.

Support or Funding Information

The present work was supported by the European Cooperation in Science and Technology (COST Action BM1203/EU‐ROS), by generous financial support by the “Stiftung Mainzer Herz”, by the Centre of Translational Vascular Biology (CTVB), by “NMFZ” and “Stufe 1” funds from the Johannes Gutenberg University Mainz.

Crosstalk between different sources of ROS and RNS (mitochondria, NADPH oxidases, xanthine oxidase and NO synthase). Superoxide/hydrogen peroxide formation by any source may be triggered by oxidative stress from all other ROS sources via redox‐activation of multiple mechanisms. From Daiber et al. BJP 2017.

Figure 1
Role of PP2A in Racial Differences in Endothelial Dysfunction
Authors: Gomez Dulce Hiraci , Aldokhayyil Maitha Hiraci , Kavazis Andreas N. , Brown Michael
Published: April 2020

Background

African Americans (AA) exhibit a higher prevalence of endothelial dysfunction and an exaggerated response to inflammatory cytokines compared to Caucasian Americans (CA). Endothelial dysfunction is characterized by a reduction in endothelial nitric oxide synthase (eNOS) activity and ultimately a lower nitric oxide production. Data obtained from bovine endothelial cells show that a reduction in eNOS activity in response to an inflammatory stimulus is mediated by protein phosphatase 2A (PP2A). Additionally, higher PP2A activity is associated with a decrease in the phosphorylation of PP2A at the Tyrosine 307 residue (p‐PP2AY307). Therefore, the purpose of this study was to investigate the role of PP2A in racial differences seen in endothelial dysfunction in response to an inflammatory stimulus.

Methods

Human umbilical vein endothelial cells (HUVECs) (n=6 cell lines; 3 CA & 3 AA) were cultured under two conditions: control or tumor necrosis factor‐α (TNF‐α) (10 ng/mL, 4 hours). Western blotting was used to measure protein expression of p‐PP2AY307, PP2A, p‐eNOSS1177 and eNOS. A two‐way ANOVA was used to assess the effects of race and conditions.

Results

No racial differences were found in the protein expression of PP2A (Fig.
) and eNOS (Fig.
) at baseline or with TNF‐α stimulation. However, AA had a lower p‐PP2AY307 expression (p=0.021; Fig.
) compared to CA HUVECs under both conditions. Additionally, AA had a lower p‐eNOSS1177 expression (p=0.008; Fig.
) compared to CA HUVECs under both condition.

Conclusion

Lower p‐PP2AY307 and p‐eNOSS1177 levels in AA endothelial cells could be attributed to an increase in PP2A activity that can ultimately inhibit eNOS phosphorylation and decrease nitic oxide production. Therefore, PP2A activity can explain, in part, racial differences observed in endothelial dysfunction and consequently cardiovascular diseases.

Support or Funding Information

Racial differences in p‐PP2AY307 and PP2A protein expression in HUVECs after 4 hours of incubation with TNF‐α (10ng/ml).

A) Densiometric quantification and representative Western blot of p‐PP2AY307 and B) Densiometric quantification and representative Western blot of PP2A. (# p= .02 in AA compared to CA HUVECs, n= 4 independent experiments. Data are shown as mean ± SEM).

Figure 1

Racial differences in p‐eNOSS1177 and eNOS protein expression in HUVECs after 4 hours of incubation with TNF‐α (10ng/ml).

A) Densiometric quantification and representative Western blot of p‐eNOSS1177 and B) Densiometric quantification and representative Western blot of eNOS. (# p= .008 in AA compared to CA HUVECs, n= 4 independent experiments. Data are shown as mean ± SEM).

Figure 2

Acknowledgements

Funded partially by AU PGOP Fellowship.
Effect of Ethanol Extract of Tetrapleura tetraptera (Schum and Thonn) Taub Leaves on Oral Glucose Tolerance in Normal, Glucose‐induced and Normotensive Female Wistar Rats
Authors: Kareem Oluwatosin Feyikemi , Ishola Ismail , Aderibigbe Olaide Ruth , Ayoola Gloria Abiodun
Published: April 2020

Traditional Medicine is reported the oldest, widely practiced healthcare system in Africa. This practice has further gained momentum in recent years due to its accessibility, affordability and extensive scientific validation. Leaves of Tetrapleura tetraptera are being used in treatment of diabetes, oxidative stress, hyperlipidemia and managing dysfunctional lipid metabolism (a side effect of the use of sulphonylureas as antidiabetics). However, there has been paucity of information on therapeutic synergy. The present study aimed to evaluate the hypoglycemic effect of Tetrapleura tetraptera ethanol leaf extract on blood glucose levels (BGL) in glucose‐induced hyperglycemic and normotensive rats. Mature female Wistar rats with average weight of 120 g were fasted for 12 h then placed into six groups of five rats each. The following treatment schedules were applied accordingly: no treatment (vehicle); glucose (2 g/kg, control); three groups of glucose‐induced hyperglycemia treated with 100 (TT100GLU), 200 (TT200GLU) and 400 (TT400GLU) mg/kg ethanol extract doses of Tetrapleura tetraptera leaves (EtTT) respectively; and 400 mg/kg extract dose of EtTT (TT400, normotensive). Blood glucose concentration through femoral vein was evaluated at 0, 30, 60, 90, 120 and 150 minutes after oral treatment in all cases. Average fasting blood glucose level in all groups at 0 min was 90± 3.71 mg/dL. All treatment groups showed an elevation in BGL at 30 min with values ranging from 86.20 ± 2.22 in vehicle to 107.4 mg/dL in TT400GLU before a progressive decrease in BGL with increase in time. The decline in BGL of treatment groups was generally not significantly different at p<0.05 from control, however, the extract significantly (p< 0.05) reduced blood glucose in normotensive group (TT400GLU) such that at 150 min, BGL dropped to 59.8 mg/dL and animals were showing symptoms of hypoglycemia. Ethanol extract of T. tetraptera leaves possesses the capacity to lower blood glucose levels thus reducing the tendency for hyperglycemic complications. These results further validate its traditional use and it can be proposed that the leaf extract dose should not be administered singly in fasting conditions as it could lead to hypoglycemia.

Support or Funding Information

I am a member of American Society for Pharmacology and Experimental Therapeutics (ASPET) with membership ID 0057705

Comparison of fasting blood glucose level of various groups. Data are expressed mean ± SEM for 6 groups of 5 rats each with significant difference tested at p<0.05

Figure 1
The Monitoring of Neurochemical Dynamics in Zebrafish Retina using Fast Scan Cyclic Voltammetry
Authors: Zestos Alexander George , Wonnenberg Pauline , Cho Whirang , Connaughton Victoria P.
Published: April 2020

Dopamine is a crucial neurotransmitter important for several behavioral, pharmacological, and disease states. Cocaine, amphetamine, and other psychostimulants elicit their effects by increasing dopamine in the extracellular space, while Parkinson’s disease is caused by the lack of extracellular dopamine due to the death of dopaminergic neurons. Techniques such as fast scan cyclic voltammetry (FSCV) have been utilized to measure extracellular dopamine and other neurotransmitters through the application of a triangle waveform, which can oxidize and, subsequently, reduce neurotransmitters at the surface of the electrode, producing a cyclic voltammogram where peak oxidative current is proportional to concentration. Utilizing FSCV with carbon fiber microelectrodes (CFMEs) is useful because the carbon electrodes are biocompatible and have both high temporal and spatial resolution. This makes the electrode amenable for the detection of neurotransmitters on a fast subsecond timescale comparable to the fast, phasic firing of dopaminergic neurons.

Preliminary studies have illustrated the utility of CFMEs with FSCV for neurochemical detection in zebrafish
(Danio rerio). CFMEs were implanted into zebrafish brain preserved in oxygenated buffer ex vivo with a micromanipulator. The electrodes were also inserted into zebrafish retina for the measurement of neurotransmitter release. The release of neurotransmitters was stimulated by the application of potassium chloride (KCl), amphetamine and cocaine, or electrical stimulation. Significant differences in dopamine levels were observed between wildtype control animals and hyperglycemic (diabetic) zebrafish. Moreover, behavioral assays such locomotor measurement displayed cognitive defects in hyperglycemic animals in addition to the thinning of the retina, which correlated to significant increases in extracellular dopamine in comparison to wildtype animals. Further work includes the examination of raclopride to increase extracellular dopamine, selective serotonin reuptake inhibitors to monitor serotonin, and desipramine to measure norepinephrine dynamics. This study allows for the further investigation of the neurochemical and behavioral effects of hyperglycemia in zebrafish. Future work will extend to the analysis of other monoamines such as serotonin and other dopamine metabolites.

Support or Funding Information

NIH STTR: 1R41NS113702‐01

Raw for the detection of dopamine in zebrafish retina after potassium chloride stimulation.

Figure 1
Stressor and Multi‐Organ Antioxidant Profile following Early Life Maternal Deprivation in Albino Rats
Authors: Obafemi Faith Ayobamidele
Published: April 2020

One‐week‐old albino pups were separated from their dams for a period of 24 to 48 hours. Sixty (60) rats were divided into 6 equal groups (n=10). Group A rats were separated for 24 hours and given glucose subcutaneously (200mg/kg) at 2, 7, 12 and 22 hours post maternal deprivation (MD). Group B rats received no intervention or treatment. Group C was subjected to 24 hours MD and given distilled water at regular intervals as group A. Group D rats had no MD but were given distilled water at same intervals as group A. Groups E and F were subjected to 48‐hour MD and administered Glucose or distilled water respectively at 2, 7, 17, 22, 27, 32, 42 and 47 hours post MD. Blood and tissue samples were collected for biochemical analyses.

Significant weight gains were recorded in the groups with no maternal deprivation. The 48‐hour MD group supplemented with glucose competed favorably, showing a 7.2% weight gain over two days. At the other end of the spectrum, the 24‐hour MD supplemented with distilled water group recorded a 3% weight loss.

The results show a graded rise in brain total protein values with time, with the highest values recorded in the 48‐hour MD + distilled water group and the lowest in the 24‐hour MD + distilled water group. Other organs showed no significant differences between groups. There were no differences across groups in all the organs assayed for nitric oxide (NO) either. For specific oxidative stress markers, Brain malondialdehyde (MDA) levels appear to be significantly lowest at the 48‐hour MD + distilled water group when compared with other groups. This correlated with a time dependent depletion in the brain antioxidant enzyme profiles studied. Brain GST, GPX and SOD all show highest concentrations in the 24‐hour MD + glucose group with lowest values recorded in the 48‐hour MD + distilled water group. Other organs did not show marked differences in between groups.

Cortisol levels were assayed to evaluate stressor responses. The highest concentrations were seen in the 48‐hour MD + glucose group with the least seen in the 24‐hour MD + distilled water group. Consequently, parenteral administration of fluids (water and glucose) are a poor substitute for maternal nutrition although initial evidence points towards potential decline in brain antioxidant profile.

Support or Funding Information

The Tertiary Education Trust Fund (TETFUND) of Nigeria. The Faculty of Veterinary Medicine, University of Abuja, Nigeria.The Cardiorenal research group, Faculty of Veterinary Medicine, University of Ibadan; especially Professor Adeolu A. Adedapo, Dr. Tayo O. Omobowale, Dr. Ademola A. Oyagbemi and Dr. Jerry Afolabi.

Brain Total Protein (TP) and Malondialdehyde (MDA) charts of all the groups

Figure 1
Role of protein kinase D1 in pulmonary hypertension in rats
Authors: Oku Shinya , Mizuno Yusuke , Sugawara Yoh , Goto Takahisa
Published: April 2020

Protein kinase D (PKD) is known to be implicated in a variety of physiological functions and pathological conditions including cardiovascular diseases, such as cardiac hypertrophy and ischemia reperfusion injury. PKD has been thought to be a new target of the diseases for treatments. Previously, we showed that PKD played a role in pulmonary arterial contraction through MYPT1 phosphorylation and actin polymerization and that inhibition of PKD activity decreased right cardiac ventricular pressure in monocrotaline‐induced pulmonary hypertension (PH) model,. In this study, we further investigated a precise role of PKD in PH and in human pulmonary smooth muscle cells (HPSMCs).

Material and methods

Eight‐week‐old male rats were given either 60 mg/kg MCT or saline 4 weeks before experiments. Isometric tension was measured using pulmonary arterial ring samples to examine the effect of PKD inhibitor, CRT0066101 on norepinephrine (NE)‐induced contraction and phosphorylation of PKD, myosin phosphatase target subunit 1 (MYPT1), regulatory myosin light chain (RLC) and other PKD substrate proteins. Expression of PKD and phosphorylated‐PKD in rats lungs were also examined with immunohistochemistry using anti‐phospho‐PKD antibodies. We also investigated precise roles of PKD isoforms using HPSMCs with RNA interference.

Results

In pulmonary arterial rings, basal expression of PKD1 and phosphorylated PKD were increased in pulmonary arteries in PH rats. NE increased phosphorylation of PKD, MYPT1 and RLC in ring samples during contraction, which were attenuated by pretreatment of CRT0066101. In immunohistochemistry, increased expression of PKD1 was observed in pulmonary arteries in PH rats (Fig
). In HASMCs, increased phosphorylation of MYPT1 and RLC with NE were significantly inhibited by PKD1 but not PKD2, 3 knock down.

Conclusions

PKD1 may play role in contraction of pulmonary arteries and at least partially via MYPT1 phosphorylation. Increased PKD1 could be involved in PH development in rats.

Support or Funding Information

Grant‐in‐Aid for Scientific Research (C) 17K11058

Immunohistochemistry with anti‐PKD antibody in lung tissue from PH rats.

Figure 1
Racial Differences in p66shc Activity in Activated Endothelial Cells
Authors: Aldokhayyil Maitha , Gomez Dulce H. , Kavazis Andreas N. , Brown Michael D.
Published: April 2020

Background

Oxidative stress plays a pivotal role in the development of endothelial dysfunction and the pathophysiology of atherosclerosis. P66shc is an adaptor protein that acts as a redox‐sensitive enzyme involved in mitochondrial reactive oxygen species (ROS) production. Upon endothelial cell activation, protein kinase C‐β2 (PKC‐β2) mediates Ser36 phosphorylation of p66shc, thereby allowing p66shc translocation from the cytosol to the mitochondria. Furthermore, we have shown that African American (AA) endothelial cells display higher levels of inflammation and oxidative stress markers compared to Caucasian American (CA) endothelial cells. Therefore, the purpose of this study was to investigate racial differences in p66shc activity in response to tumor necrosis factor‐α (TNF‐α)‐induced endothelial cell activation.

Methods

Human umbilical vein endothelial cells (HUVECs) from three AA donors and three CA donors were cultured and incubated with TNF‐α (10ng/ml, 4hr) to assess racial differences in p66shc, PKC‐β2 and endothelial nitric oxide synthase (eNOS) protein levels and bioactivity.

Results

Enzymatically active eNOS (p‐eNOSS1177) was significantly lower in AA HUVECs under both basal and TNF‐α incubation conditions (p= 0.01, Fig.
). Additionally, p‐Ser36 p66shc/total p66shc was significantly lower in AA HUVECs compared to CA HUVECs (p= 0.04, Fig. 3C). However, there was no group or treatment effect on any on the other variables measured.

Conclusion

p66shc represents an important molecular pathway that mediates ROS production and plays an integral role in the development of cardiovascular disease. According to our results, racial differences in endothelial function cannot be explained by p66shc. However, future research should focus on assessing cytosolic vs. mitochondrial p66shc levels in AA endothelial cells compared to CA.

eNOS protein expression and bioactivity in CA and AA HUVECs after 4 hours of incubation with TNF‐α (10ng/ml).

A) Densiometric quantification and representative Western blot of p‐eNOS. B) Densiometric quantification and representative Western blot of eNOS. C) p‐eNOS bioactivity. (* p= .01 vs. CA HUVECs, n= 4 independent experiments. Data are shown as mean ± SEM).

Figure 1

p66shc protein expression and bioactivity in CA and AA HUVECs after 4 hours of incubation with TNF‐α (10ng/ml).

A) Densiometric quantification and representative Western blot of p‐p66shc. B) Densiometric quantification and representative Western blot of p66shc. C) p‐p66shc bioactivity. (* p= .04 vs. CA HUVECs, n= 4 independent experiments. Data are shown as mean ± SEM).

Figure 2
Piezo‐electric based Ultraprecise/Ultratrace 3D Food Printing of Potato Resistant Starch
Authors: Oh Yourim , Lee Nam Keun , Rhee Jin-Kyu
Published: April 2020

Recently, compared to traditional food production systems, 3D food printing has gained a lot of interest because of the potential benefits of being able to customized food products fabrication in colour, shape, texture, flavor and even nutrition. Successful printing of food objects in 3D food printing is critical, and high accuracy and precision food printing technology is required to reproduce delicate and complex food 3D structures. In 3D food printing, the properties of food materials, such as rheological properties, chemical properties and thermal stability, are significant for the structure accuracy and precision of printed objects. In this study, we tried to present a 3D structure layering method for potato resistant starch using drop‐on‐demand (DOD) printing method (piezoelectric system type) that can express the fine structure of food by inkjet printing technology. Nanocrystals cellulose (CNC) and sodium alginate (AS) were used to form a food 3D structure, and 3D printing optimal ink formulation ratio of CNC and AS (CNC:AS=80:20) was selected through preliminary experiments. The purpose of this study was to determine the possibility of 3D printing and printability after comparing rheological properties of mixtures with and without annealing by varying the content of potato resistant starch (PRS) in the mixture of CNC and AS. 3D food structure with various combination of potato resistant starch (RS) to a mixture of CNC and AS was printed, and compared the rheological properties of the mixture that had not been temperature‐treated and the one that had been annealed. After that, the optimal material combination for precise 3D printing was explored together with the physical properties of the printed object.

Support or Funding Information

This research was supported in part by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education (2018R1D1A1B07045349), the High Value‐added Food Technology Development Program, the Ministry of Agriculture, Food and Rural Affairs (MAFRA), Republic of Korea (118059‐2) and the Ewha Womans University Research Grant of 2019.

Piezo‐electric based Ultraprecise/Ultratrace 3D Food Printing

Figure 1
Treatment of Sleep Disordered Breathing With Leptin Loaded Exosomes
Authors: Pho Huy , Freire Carla , Kojima Ryo , Berger Slava , Ramsey Jacob D. , Batrakova Elena V. , Kabanov Alexander V. , Polotsky Vsevolod Y.
Published: April 2020

Rationale

Severe obesity leads to two types of sleep disordered breathing, including more prevalent obstructive sleep apnea (OSA), recurrent obstruction of the upper airway during sleep, and obesity hypoventilation syndrome (OHS) caused by impaired central nervous system responses to CO2. Adipokine leptin suppresses food intake, increases metabolic rate, stimulates breathing and ventilatory responses to CO2, and activates pharyngeal muscles improving upper airway patency during sleep. However, diet‐induced obesity (DIO) causes leptin resistance due to reduced permeability of the blood‐brain barrier (BBB) for leptin. Recent work with exosomes as nanocarriers for drug delivery vehicles have shown the possibility of overcoming the BBB to deliver therapeutic agents. We hypothesize that leptin loaded exosomes overcome BBB and treat OSA and OHS in DIO mice.

Methods

Male DIO mice (n=6) were head mounted with EEG and EMG leads. Polysomnogram in the barometric plethysmography chamber was performed with IV administration of saline, free leptin, empty exosomes, and leptin loaded exosomes one week apart in a randomized cross‐over manner. Minute ventilation (VE) was measured through sleep/wake states and normalized to body weight. Upper airway obstruction was defined by the presence of inspiratory airflow limitation (IFL), as characterized by an early inspiratory plateau in airflow at a maximum level (VImax) while effort continued to increase.

Results

As we have shown previously, DIO mice treated with placebo demonstrated upper airway obstruction, especially during REM sleep, and hypoventilation throughout both NREM and REM sleep. Leptin loaded exosomes nearly doubled VImax (p<0.05) and induced an approximately 1.8 increase in VE in REM IFL (p<0.05) compared to the IV saline, IV leptin, and empty exosome groups (Figure
), suggesting that upper airway obstruction was relieved. In addition, leptin loaded exosomes significantly increased VE during non‐flow limited breathing (p<0.05) compared to all other groups.

Conclusion

Exosomal leptin delivery increased ventilation during both non‐flow limited breathing and flow limited breathing, suggesting a stimulatory effect on control of breathing and upper airway patency. Our results indicate that exosomal leptin can be considered for OSA and OHS pharmacotherapy in obesity.

Leptin loaded exosomes presented increased ventilation in diet‐induced obese mice. Maximal inspiratory flow (VImax; mL/s). Minute ventilation normalized to body weight (nVE; mL/min/g).

Figure 1