scholarly journals Reduced stability and pH-dependent activity of a common obesity-linked PCSK1 polymorphism, N221D

Endocrinology ◽  
2019 ◽  
Author(s):  
Timothy S Jarvela ◽  
Surbhi Gahlot ◽  
Manita Shakya ◽  
Tomas Bachor ◽  
Anne White ◽  
...  
Keyword(s):  
High Fat Diet ◽  
Obesity Risk ◽  
Wild Type ◽  
Prohormone Convertase 1 ◽  
Cell Clones ◽  
Increased Risk ◽  
Dependent Activity ◽  
Peptide Precursors ◽  
Pcsk1 Gene ◽  
Golgi Network

Abstract Common mutations in the human prohormone convertase 1/3 (PC1/3) gene (PCSK1) are linked to increased risk of obesity. Previous work has shown that the rs6232 SNP (N221D) results in slightly decreased activity, though whether this decrease underlies obesity risk is not clear. We observed significantly decreased activity of the N221D PC1/3 enzyme at the pH of the trans-Golgi network; at this pH, the mutant enzyme was less stable than wild-type enzyme. Recombinant N221D PC1/3 also showed enhanced susceptibility to heat stress. Enhanced susceptibility to tunicamycin-induced ER stress was observed in AtT-20/PC2 cell clones in which murine PC1/3 was replaced by human N221D PC1/3, as compared to wild-type human PC1/3. However, N221D PC1/3-expressing AtT-20/PC2 clones processed proopiomelanocortin to α-MSH similarly to wild-type PC1/3. We also generated a CRISPR-edited mouse line expressing the N221D mutation in the Pcsk1 gene. When homozygous N221D mice were fed either a standard or a high fat diet, we found no increase in body weight compared to their wild-type sibling controls. Sexual dimorphism was observed in pituitary ACTH for both genotypes, with females exhibiting lower levels of pituitary ACTH. In contrast, hypothalamic α−MSH content for both genotypes was higher in females compared to males. Hypothalamic CLIP content was higher in wild-type females compared to wild-type, but not N221D, males. Together, these data suggest that the increased obesity risk linked to the N221D allele in humans may be due in part to PC1/3-induced loss of resilience to stressors rather than strictly to decreased enzymatic activity on peptide precursors.

Induction of ER stress by variants of the prohormone convertase 1 (PCSK1)-gene

2013 ◽  
Vol 8 (S 01) ◽  
Author(s):  
S Behrendt ◽  
D Löffler ◽  
R Tauscher ◽  
A Körner
Keyword(s):  
Er Stress ◽  
Prohormone Convertase ◽  
Prohormone Convertase 1 ◽  
Pcsk1 Gene

Non-Fasting Factor VII Coagulant Activity (FVII:C) Increased by High-Fat Diet

1994 ◽  
Vol 71 (06) ◽  
pp. 755-758 ◽  
Author(s):  
E M Bladbjerg ◽  
P Marckmann ◽  
B Sandström ◽  
J Jespersen
Keyword(s):  
High Fat Diet ◽  
Fat Content ◽  
Factor Vii ◽  
Amidolytic Activity ◽  
High Fat ◽  
Low Fat Diet ◽  
Increased Risk ◽  
Coagulant Activity ◽  
High Fat Diets ◽  
Fat Diets

SummaryPreliminary observations have suggested that non-fasting factor VII coagulant activity (FVII:C) may be related to the dietary fat content. To confirm this, we performed a randomised cross-over study. Seventeen young volunteers were served 2 controlled isoenergetic diets differing in fat content (20% or 50% of energy). The 2 diets were served on 2 consecutive days. Blood samples were collected at 8.00 h, 16.30 h and 19.30 h, and analysed for triglycerides, FVII coagulant activity using human (FVII:C) or bovine thromboplastin (FVII:Bt), and FVII amidolytic activity (FVIPAm). The ratio FVII:Bt/FVII:Am (a measure of FVII activation) increased from fasting levels on both diets, but most markedly on the high-fat diet. In contrast, FVII: Am (a measure of FVII protein) tended to decrease from fasting levels on both diets. FVII:C rose from fasting levels on the high-fat diet, but not on the low-fat diet. The findings suggest that high-fat diets increase non-fasting FVII:C, and consequently may be associated with increased risk of thrombosis.

The Effect of Mianserin on Lifespan of Caenorhabditis elegans is Abolished by Glucose

2021 ◽  
Vol 13 ◽  
Author(s):  
Abdullah Almotayri ◽  
Jency Thomas ◽  
Mihiri Munasinghe ◽  
Markandeya Jois
Keyword(s):  
Caenorhabditis Elegans ◽  
Scaffolding Protein ◽  
Lifespan Extension ◽  
Wild Type ◽  
E Coli ◽  
C Elegans ◽  
Risk Of Death ◽  
Increased Risk ◽  
Antidepressant Use ◽  
Extension Effect

Background: The antidepressant mianserin has been shown to extend the lifespan of Caenorhabditis elegans (C. elegans), a well-established model organism used in aging research. The extension of lifespan in C. elegans was shown to be dependent on increased expression of the scaffolding protein (ANK3/unc-44). In contrast, antidepressant use in humans is associated with an increased risk of death. The C. elegans in the laboratory are fed Escherichia coli (E. coli), a diet high in protein and low in carbohydrate, whereas a typical human diet is high in carbohydrates. We hypothesized that dietary carbohydrates might mitigate the lifespan-extension effect of mianserin. Objective: To investigate the effect of glucose added to the diet of C. elegans on the lifespan-extension effect of mianserin. Methods: Wild-type Bristol N2 and ANK3/unc-44 inactivating mutants were cultured on agar plates containing nematode growth medium and fed E. coli. Treatment groups included (C) control, (M50) 50 μM mianserin, (G) 73 mM glucose, and (M50G) 50 μM mianserin and 73 mM glucose. Lifespan was determined by monitoring the worms until they died. Statistical analysis was performed using the Kaplan-Meier version of the log-rank test. Results: Mianserin treatment resulted in a 12% increase in lifespan (P<0.05) of wild-type Bristol N2 worms but reduced lifespan by 6% in ANK3/unc-44 mutants, consistent with previous research. The addition of glucose to the diet reduced the lifespan of both strains of worms and abolished the lifespan-extension by mianserin. Conclusion: The addition of glucose to the diet of C. elegans abolishes the lifespan-extension effects of mianserin.

scholarly journals Emotional Eating in Adolescence: Effects of Emotion Regulation, Weight Status and Negative Body Image

Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 79
Author(s):  
Lenka H. Shriver ◽  
Jessica M. Dollar ◽  
Susan D. Calkins ◽  
Susan P. Keane ◽  
Lilly Shanahan ◽  
...  
Keyword(s):  
Body Image ◽  
Emotion Regulation ◽  
Emotional Regulation ◽  
Emotional Eating ◽  
Weight Status ◽  
Normal Weight ◽  
Linear Regression Models ◽  
Obesity Risk ◽  
Negative Body Image ◽  
Increased Risk

Emotional eating is associated with an increased risk of binge eating, eating in the absence of hunger and obesity risk. While previous studies with children and adolescents suggest that emotion regulation may be a key predictor of this dysregulated eating behavior, little is known about what other factors may be influencing the link between emotional regulation and emotional eating in adolescence. This multi-method longitudinal study (n = 138) utilized linear regression models to examine associations between childhood emotion regulation, adolescent weight status and negative body image, and emotional eating at age 17. Emotion regulation predicted adolescent emotional eating and this link was moderated by weight status (β = 1.19, p < 0.01) and negative body image (β = −0.34, p < 0.01). Higher engagement in emotional eating was predicted by lower emotional regulation scores among normal-weight teens (β = −0.46, p < 0.001) but not among overweight/obese teens (β = 0.32, p > 0.10). Higher scores on emotion regulation were significantly associated with lower emotional eating at high (β = −1.59, p < 0.001) and low (β = −1.00, p < 0.01) levels of negative body image. Engagement in emotional eating was predicted by higher negative body image among overweight/obese teens only (β = 0.70, p < 0.001). Our findings show that while better childhood emotion regulation skills are associated with lower emotional eating, weight status and negative body image influence this link and should be considered as important foci in future interventions that aim to reduce emotional eating in adolescence.

scholarly journals Effects of B.1.1.7 and B.1.351 on COVID-19 Dynamics: A Campus Reopening Study

2021 ◽  
Author(s):  
Kevin Linka ◽  
Mathias Peirlinck ◽  
Amelie Schäfer ◽  
Oguz Ziya Tikenogullari ◽  
Alain Goriely ◽  
...  
Keyword(s):  
Online Education ◽  
The United States ◽  
Wild Type ◽  
Seir Model ◽  
Population Mixing ◽  
Santa Clara County ◽  
Increased Risk ◽  
Controversial Topic ◽  
Almost All ◽  
Local Reproduction

AbstractThe timing and sequence of safe campus reopening has remained the most controversial topic in higher education since the outbreak of the COVID-19 pandemic. By the end of March 2020, almost all colleges and universities in the United States had transitioned to an all online education and many institutions have not yet fully reopened to date. For a residential campus like Stanford University, the major challenge of reopening is to estimate the number of incoming infectious students at the first day of class. Here we learn the number of incoming infectious students using Bayesian inference and perform a series of retrospective and projective simulations to quantify the risk of campus reopening. We create a physics-based probabilistic model to infer the local reproduction dynamics for each state and adopt a network SEIR model to simulate the return of all undergraduates, broken down by their year of enrollment and state of origin. From these returning student populations, we predict the outbreak dynamics throughout the spring, summer, fall, and winter quarters using the inferred reproduction dynamics of Santa Clara County. We compare three different scenarios: the true outbreak dynamics under the wild-type SARS-CoV-2, and the hypothetical outbreak dynamics under the new COVID-19 variants B.1.1.7 and B.1.351 with 56% and 50% increased transmissibility. Our study reveals that even small changes in transmissibility can have an enormous impact on the overall case numbers. With no additional countermeasures, during the most affected quarter, the fall of 2020, there would have been 203 cases under baseline reproduction, compared to 4727 and 4256 cases for the B.1.1.7 and B.1.351 variants. Our results suggest that population mixing presents an increased risk for local outbreaks, especially with new and more infectious variants emerging across the globe. Tight outbreak control through mandatory quarantine and test-trace-isolate strategies will be critical in successfully managing these local outbreak dynamics.

scholarly journals Novel regulation of renal gluconeogenesis by Atp6ap2 in response to high fat diet via PGC1-α/AKT-1 pathway

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Safia Akhtar ◽  
Silas A. Culver ◽  
Helmy M. Siragy
Keyword(s):  
Protein Expression ◽  
High Fat Diet ◽  
Normal Diet ◽  
Receptor Expression ◽  
Wild Type ◽  
High Fat ◽  
Renal Gluconeogenesis ◽  
Mrna And Protein Expression ◽  
Polymerase Chain ◽  
Renal Expression

AbstractRecent studies suggested that renal gluconeogenesis is substantially stimulated in the kidney in presence of obesity. However, the mechanisms responsible for such stimulation are not well understood. Recently, our laboratory demonstrated that mice fed high fat diet (HFD) exhibited increase in renal Atp6ap2 [also known as (Pro)renin receptor] expression. We hypothesized that HFD upregulates renal gluconeogenesis via Atp6ap2-PGC-1α and AKT pathway. Using real-time polymerase chain reaction, western blot analysis and immunostaining, we evaluated renal expression of the Atp6ap2 and renal gluconeogenic enzymes, PEPCK and G6Pase, in wild type and inducible nephron specific Atp6ap2 knockout mice fed normal diet (ND, 12 kcal% fat) or a high-fat diet (HFD, 45 kcal% fat) for 8 weeks. Compared with ND, HFD mice had significantly higher body weight (23%) (P < 0.05), renal mRNA and protein expression of Atp6ap2 (39 and 35%), PEPCK (44 and 125%) and G6Pase (39 and 44%) respectively. In addition, compared to ND, HFD mice had increased renal protein expression of PGC-1α by 32% (P < 0.05) and downregulated AKT by 33% (P < 0.05) respectively in renal cortex. Atp6ap2-KO abrogated these changes in the mice fed HFD. In conclusion, we identified novel regulation of renal gluconeogenesis by Atp6ap2 in response to high fat diet via PGC1-α/AKT-1 pathway.

scholarly journals 12/15-Lipoxygenase signaling in the endoplasmic reticulum stress response

2012 ◽  
Vol 302 (6) ◽  
pp. E654-E665 ◽  
Author(s):  
Banumathi K. Cole ◽  
Norine S. Kuhn ◽  
Shamina M. Green-Mitchell ◽  
Kendall A. Leone ◽  
Rebekah M. Raab ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Endoplasmic Reticulum ◽  
Stress Response ◽  
Er Stress ◽  
Pancreatic Islets ◽  
High Fat Diet ◽  
Wild Type ◽  
High Fat ◽  
Stress Markers ◽  
Deficient Mice

Central obesity is associated with chronic inflammation, insulin resistance, β-cell dysfunction, and endoplasmic reticulum (ER) stress. The 12/15-lipoxygenase enzyme (12/15-LO) promotes inflammation and insulin resistance in adipose and peripheral tissues. Given that obesity is associated with ER stress and 12/15-LO is expressed in adipose tissue, we determined whether 12/15-LO could mediate ER stress signals. Addition of 12/15-LO lipid products 12(S)-HETE and 12(S)-HPETE to differentiated 3T3-L1 adipocytes induced expression and activation of ER stress markers, including BiP, XBP-1, p-PERK, and p-IRE1α. The ER stress inducer, tunicamycin, upregulated ER stress markers in adipocytes with concomitant 12/15-LO activation. Addition of a 12/15-LO inhibitor, CDC, to tunicamycin-treated adipocytes attenuated the ER stress response. Furthermore, 12/15-LO-deficient adipocytes exhibited significantly decreased tunicamycin-induced ER stress. 12/15-LO action involves upregulation of interleukin-12 (IL-12) expression. Tunicamycin significantly upregulated IL-12p40 expression in adipocytes, and IL-12 addition increased ER stress gene expression; conversely, LSF, an IL-12 signaling inhibitor, and an IL-12p40-neutralizing antibody attenuated tunicamycin-induced ER stress. Isolated adipocytes and liver from 12/15-LO-deficient mice fed a high-fat diet revealed a decrease in spliced XBP-1 expression compared with wild-type C57BL/6 mice on a high-fat diet. Furthermore, pancreatic islets from 12/15-LO-deficient mice showed reduced high-fat diet-induced ER stress genes compared with wild-type mice. These data suggest that 12/15-LO activity participates in ER stress in adipocytes, pancreatic islets, and liver. Therefore, reduction of 12/15-LO activity or expression could provide a new therapeutic target to reduce ER stress and downstream inflammation linked to obesity.

scholarly journals CD40L controls obesity-associated vascular inflammation, oxidative stress, and endothelial dysfunction in high fat diet-treated and db/db mice

2017 ◽  
Vol 114 (2) ◽  
pp. 312-323 ◽  
Author(s):  
Sebastian Steven ◽  
Mobin Dib ◽  
Michael Hausding ◽  
Fatemeh Kashani ◽  
Matthias Oelze ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Endothelial Dysfunction ◽  
High Fat Diet ◽  
Immune Cell ◽  
Vascular Inflammation ◽  
Human Study ◽  
Isometric Tension ◽  
Wild Type ◽  
High Fat ◽  
Aorta Ascendens

Abstract Aims CD40 ligand (CD40L) signaling controls vascular oxidative stress and related dysfunction in angiotensin-II-induced arterial hypertension by regulating vascular immune cell recruitment and platelet activation. Here we investigated the role of CD40L in experimental hyperlipidemia. Methods and results Male wild type and CD40L−/− mice (C57BL/6 background) were subjected to high fat diet for sixteen weeks. Weight, cholesterol, HDL, and LDL levels, endothelial function (isometric tension recording), oxidative stress (NADPH oxidase expression, dihydroethidium fluorescence) and inflammatory parameters (inducible nitric oxide synthase, interleukin-6 expression) were assessed. CD40L expression, weight, leptin and lipids were increased, and endothelial dysfunction, oxidative stress and inflammation were more pronounced in wild type mice on a high fat diet, all of which was almost normalized by CD40L deficiency. Similar results were obtained in diabetic db/db mice with CD40/TRAF6 inhibitor (6877002) therapy. In a small human study higher serum sCD40L levels and an inflammatory phenotype were detected in the blood and Aorta ascendens of obese patients (body mass index > 35) that underwent by-pass surgery. Conclusion CD40L controls obesity-associated vascular inflammation, oxidative stress and endothelial dysfunction in mice and potentially humans. Thus, CD40L represents a therapeutic target in lipid metabolic disorders which is a leading cause in cardiovascular disease.

scholarly journals Does early onset asthma increase childhood obesity risk? A pooled analysis of 16 European cohorts

2018 ◽  
Vol 52 (3) ◽  
pp. 1800504 ◽  
Author(s):  
Zuelma A. Contreras ◽  
Zhanghua Chen ◽  
Theano Roumeliotaki ◽  
Isabella Annesi-Maesano ◽  
Nour Baïz ◽  
...  
Keyword(s):  
Allergic Rhinitis ◽  
Childhood Asthma ◽  
Early Onset ◽  
Pooled Analysis ◽  
Obesity Risk ◽  
Obese Children ◽  
The Past ◽  
Increased Risk ◽  
The Uk

The parallel epidemics of childhood asthma and obesity over the past few decades have spurred research into obesity as a risk factor for asthma. However, little is known regarding the role of asthma in obesity incidence. We examined whether early-onset asthma and related phenotypes are associated with the risk of developing obesity in childhood.This study includes 21 130 children born from 1990 to 2008 in Denmark, France, Germany, Greece, Italy, The Netherlands, Spain, Sweden and the UK. We followed non-obese children at 3–4 years of age for incident obesity up to 8 years of age. Physician-diagnosed asthma, wheezing and allergic rhinitis were assessed up to 3–4 years of age.Children with physician-diagnosed asthma had a higher risk for incident obesity than those without asthma (adjusted hazard ratio (aHR) 1.66, 95% CI 1.18–2.33). Children with active asthma (wheeze in the last 12 months and physician-diagnosed asthma) exhibited a higher risk for obesity (aHR 1.98, 95% CI 1.31–3.00) than those without wheeze and asthma. Persistent wheezing was associated with increased risk for incident obesity compared to never wheezers (aHR 1.51, 95% CI 1.08–2.09).Early-onset asthma and wheezing may contribute to an increased risk of developing obesity in later childhood.

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