bluuebunny/crossref_metadata_2025 huggingface dataset:
Survival and Growth of C57BL/6J Mice Lacking the BK Channel (KCa1.1): Lower Adult Body Weight Occurs together with Higher Body Fat
Authors: Halm Susan T. , Halm Dan R.
Published: November 2023

The BK potassium channel contributes to K+ flow and the electrical behavior of many cell types: including pancreatic β‐cells and cells in the hypothalamic‐pituitary‐adrenal axis. Mice made null for the gene (Kcnma1, slo‐1) producing the BK channel exhibit numerous deficits in physiological functions, but also show resistance toward developing obesity on a high fat diet (Illison J, et al, Diabetes 2016 db160245). Initial breeding pairs lacking a single allele of Kcnma1 (BKhet) in a C57BL/6J background strain were obtained from Dr. Andrea Meredith at the University of Maryland. A colony derived by breeding these heterozygous mice had litter sizes of ~8 pups, 53% male. For the period of maternal care (P0 – P21) pup death peaked at P1 with a second less severe interval of pup death peaking near P13. The later deaths (~P13) of pups null for Kcnma1 (BKKO) were greater than Mendelian expectations. Pup death at ~P1 was twice as likely during the 20 month construction of a building adjacent to the animal facility compared with the quiescent period after cessation of construction. Births also were not consistent with Mendelian predictions, indicating a specific prenatal disadvantage for female BKKO mice in the quiescent period and for female BKhet mice during construction, a change likely induced by this environmental stressor. Death of colony mice after weaning was rare (~0.5%). After weaning, weight gain was lower for BKKO mice compared with wild‐type littermates: male BKKO mice were 5 g smaller and female BKKO mice were 4 g smaller. Lower weight gain for BKKO mice compared to wild‐type occurred in part due to an event of weight loss during the early post‐weaning period, between weeks 3 to 9. Interestingly, wild‐type mice as well as male BKKO mice were ~1 g larger during construction compared with mice during quiescence. Body composition determined by quantitative magnetic resonance (QMR) indicated a higher fat proportion for wild‐type female mice compared with males, as well as a higher hydration ratio (total water mass – free water mass/lean mass). Comparison of lean, fat, and water components for female and male mice suggested an interrelationship that governs changes to body composition. Both male and female BKKO mice showed higher fat proportions than wild‐type, with the female BKKO mice exhibiting a larger variation in fat content and male BKKO mice having a higher hydration ratio than wild‐type. Together these results indicate that BKKO mice suffered disadvantages that led to prenatal and perinatal death. A metabolic difference likely related to glucose handling led to the smaller body size and distinct composition with higher fat for BKKO mice, suggesting a diversion of energy supplies from growth to fat storage.

Support or Funding Information

[NIH DK65845; WSU‐BSoM Seed Grant]
Plasticity of TRPV1‐dependent Neurotransmission in the Paraventricular Nucleus of db/db Mice
Authors: Gao Hong , Miyada Kayoko , Qiao Xin , Molinas Adrien JR , Zsombok Andrea
Published: November 2023

Transient receptor potential vanilloid type 1 (TRPV1) has been shown to play a role in the modulation of glucose homeostasis. Preautonomic, liver‐related neurons in the paraventricular nucleus (PVN) of the hypothalamus contribute to the regulation of sympathetic and parasympathetic outflow to the liver. Our previous findings demonstrated that liver‐related PVN neurons are controlled by TRPV1‐dependent excitatory neurotransmission. In this study, liver‐related PVN neurons were identified with a retrograde, trans‐neuronal viral tracer and whole‐cell patch‐clamp recordings were conducted. We tested the hypothesis that the TRPV1‐dependent synaptic control of liver‐related PVN neurons is reduced in db/db mice. Application of the exogenous TRPV1 agonist, capsaicin (1μM) increased the average frequency of miniature excitatory post‐synaptic currents (mEPSCs) in liver‐related PVN neurons from lean mice. In contrast, in db/db mice capsaicin application did not change the overall frequency of mEPSCs. Capsaicin did not alter the frequency of miniature inhibitory post‐synaptic currents (mIPSCs) neither in lean or db/db mice. We did not observe significant difference in the basal frequency of mEPSCs and mIPSCs in liver‐related PVN neurons of lean and db/db mice. On the other hand, the amplitude of mIPSCs was smaller in liver‐related PVN neurons of db/db mice compared with lean mice. GABAA‐mediated inhibitory tonic currents as bicuculline‐dependent inward shift of the holding current were also revealed in liver‐related PVN neurons. Our data did not show difference in the magnitude of tonic inhibition between the groups. Together, this study suggests that the TRPV1‐dependent control of liver‐related PVN neurons is diminished in db/db mice. These findings are consistent with our previous data demonstrating synaptic plasticity of hypothalamic autonomic circuits in hyperglycemic conditions, and further suggest dysregulation of neuronal activity at the level of the PVN in obese‐diabetic state.

Support or Funding Information

Supported by NIDDK R01DK099598
Neuregulin‐1 Decreases Hepatic Glucose Production in db/db Mice
Authors: Sirvent Pascal , Teixeira Allison , Etienne Monique , Delcros Geoffrey , Lantier Louise , McGuinness Owen P , Otero Yolanda Fernandez
Published: November 2023

Background and aims

Previous studies from our laboratory had shown that neuregulin‐1 (NRG1) has a role in glucose homeostasis, improving glucose tolerance in db/db mice. A predominant role of the liver has been suggested, since NRG1 receptors were activated only in the hepatic tissue, but not in skeletal muscle or adipose tissue. Our aim was to study whole body insulin sensitivity and hepatic response to an acute treatment with NRG1.

Methods

Three hour fasted 9‐week old db/db mice were injected with NRG1 (50μg/kg) or saline (SAL) as control. After 2h, a hyperinsulinemic‐euglycemic clamp was performed. A different group under the same conditions, was used to study hepatic signalling after the NRG1 or SAL injection.

Results

Two hours after injection, insulin levels were lower in db/db mice injected with NRG1 (38±9 SAL vs 18±4 NRG1, ng/ml). As consequence, this group of mice showed lower glucose infusion rate (GIR) during the clamp (21±2 SAL vs 13±3 NRG1, mg/kg·min). Despite lower insulin levels, glucose turnover (Rd) and hepatic glucose production (endo‐Ra) were significantly decreased in the presence of NRG1 (Rd: 32±3 SAL vs 24±2 NRG1, mg/kg·min. EndoRa: 10±1 SAL vs 7±1 NRG1, p<0.05; mg/kg·min). Tissue‐specific glucose uptake was not different.

Liver Akt phosphorylation (Ser 473) ratio was significantly higher in db/db mice 2h after NRG1 treatment (1±0.4 SAL vs 4.5±0.9 NRG1, p<0.05, arbitrary units). GSK3‐β phosphorylation (Ser9) ratio was not different. Hepatic gene expression of G6pc was lower in db/db mice treated with NRG1 (Rq 1±0.03 SAL vs 0.6±0.1 NRG1). Hepatic glycogen content was not different among groups.

Conclusions

Acute (2h) treatment with neuregulin‐1 caused a decrease in insulin levels, glucose turnover, and hepatic glucose production during the hyperinsulinemic‐euglycemic clamp. The stronger inhibition in endo‐Ra with lower insulin levels, may reflect an increase in hepatic insulin sensitivity and/or a direct effect of NRG1 on hepatic glucose production. The increased Akt phosphorylation ratio and decreased G6pc gene expression could be involved in the mechanism used by NRG1.

Support or Funding Information

This work has been supported by a grant from Université Blaise Pascal.
Angiotensin‐II Type 1a Receptor Present in Insulin Producing Cells is Essential for Normal Islet Function
Authors: Chodavarapu Harshita , Xu Jiaxi , Lazartigues Eric
Published: November 2023

The renin angiotensin system (RAS) has been proposed to regulate glucose homeostasis, notably by modulating insulin secretion. Insulin is produced both by β‐cells in the pancreas and neurons in the brain. However, while Angiotensin‐II type 1a receptors (AT1R) are expressed on both cell types, their specific role in insulin secretion remains unclear. To investigate this nebulous area, we generated specific knockout mice for 1) AT1R on insulin‐producing cells (IC): neurons and β‐cells (IC‐AT1R KO: AT1R floxed bred with Ins2‐cre mice) and 2) AT1R on neurons only (N‐AT1R KO: AT1R floxed bred with synapsin‐cre mice). With respect to the first model, the aim of this study is to elucidate the role of IC‐specific AT1R in the regulation of β‐cell dysfunction in regular diet (RD)‐fed and high fat diet (HFD)‐fed male mice. We used 5–6 weeks old conditional IC‐AT1R KO mice and control littermates (CT), fed them HFD for 3 months and isolated pancreatic islets at the end of the study for further analysis. After 3 months of HFD feeding, CT mice demonstrated increased body weight (HFD: 41±2.1 vs. RD: 28±0.6 g), hyperglycemia (HFD: 154.3±6.2 vs. RD: 108.5±13.23 mg/dl), glucose intolerance (HFD: 48488±5843 vs. RD: 25950±2224 AUC) and β‐cell dysfunction. These changes in glucose homeostasis were associated with a 1.5 fold increase in AT1R mRNA expression, marker of overactive RAS, and 4.3 fold increase in the autophagy marker, LC3II, in the islets of CT HFD‐fed compared to CT RD‐fed mice. On the other hand, both RD‐fed and HFD‐fed IC‐AT1R KO mice displayed β‐cell dysfunction and glucose intolerance (IC‐AT1R KO RD: 39784±4088 vs. CT‐RD: 25950±2224; IC‐AT1R KO HFD: 47502±4782 vs. CT HFD: 48488±5843 AUC) but had normal fasting blood glucose levels (IC‐AT1R KO RD: 97.5±6.4 vs. CT RD: 108.5±13.23; IC‐AT1R KO HFD: 97.4±3.7 vs. CT HFD: 154.3±6.2 mg/dl) and body weights (IC‐AT1R KO RD: 28.6±1.0 vs. CT RD: 28±0.6; IC‐AT1R KO HFD: 34.82±1.6 vs. CT HFD: 41±2.1 g). Furthermore, there was a 5.4 fold increase in islet LC3II protein expression in IC‐AT1R KO‐RD mice compared to CT‐RD mice. In addition, HFD‐fed IC‐AT1R KO mice demonstrated further increase in LC3II expression (1.5 fold vs. IC‐AT1R KO‐RD and 1.9 fold vs. CT‐HFD).

Altogether, this is the first study to demonstrate that AT1R present in insulin producing neurons and β‐cells is essential for the maintenance of normal β‐cell function. In addition, our study also sheds light on islet autophagy as a potential mechanistic link between IC specific AT1R and β‐cell dysfunction. However, further studies are required to clarify whether autophagy is upstream/downstream to AT1R and to separate central and peripheral mechanisms.

Support or Funding Information

American Heart Association: 12EIA8030004 and 14PRE18830012.
Toxin‐antitoxin systems: novel mechanisms of toxin activity and antitoxin inhibition
Authors: Page Rebecca , Peti Wolfgang
Published: November 2023

Toxin‐antitoxin (TA) modules function as regulatory switches that allow bacteria to adapt to rapidly changing environments. Under conditions of unrestrained growth, these systems are repressed. However, under conditions of stress, these systems are activated, leading to growth arrest and dormancy. Their central role controlling bacterial growth has led to renewed efforts to understand the molecular basis of TA function in order to develop strategies to exploit these systems for societal benefit. The E. coli mqsR gene was originally discovered for its role in promoting biofilm formation and dormancy. During the past five years, we have used biochemistry and structural biology to show that mqsRA is a bona fide toxin‐antitoxin system, in which MqsR is ribonuclease (RNase) toxin, and MqsA is its cognate antitoxin. Unpublished results from our group now demonstrate that MqsR defines a new hybrid family of toxin RNases and that its MqsA antitoxin inhibits MqsR via a novel mechanism. Specifically, we are using NMR chemical shift mapping coupled with mutagenesis and biochemistry to identify the residues that mediate mRNA binding and cleavage and show that MqsR exhibits sequence specificity outside the primary GCU cleavage sequence. Furthermore, our work is revealing that MqsA inhibits MqsR activity via a completely novel mechanism for antitoxins; i.e. it potentially inhibits substrate binding by engaging loops outside the MqsR active site that are critical for the interaction with mRNA. Finally, we extending these studies to evolutionarily related families to elucidate the molecular basis of conservation and divergence of enzyme function in this family. Collectively, these studies are not only revealing that MqsRA defines a novel subfamily of TA systems but, more critically, also leading to the identification of the key molecular details that will allow these systems to be directed for societal benefit.

Support or Funding Information

NSF‐CAREER award (MCB0952550) to RP.
HIF1α Activated Etv2 and Notch1 Signaling Biphasically Mediates ESC Differentiation to Arterial Endothelial Cells with Enhanced Sequestration in Ischemic Tissue
Authors: Hyun James , Tsang Kitman , Cheng Kwong , Vargas Micaela , Komarova Yulia , Mehta Dolly , Fukai Masuko , Rehman Jalees , Malik Asrar
Published: November 2023

Endothelial progenitors derived from embryonic stem cells (ESCs) are an effective and attractive source to treat ischemic tissue. However, the molecular mechanisms mediating the generation of these beneficial cells and their regenerative capacity have not been well characterized. In this study, we demonstrate hypoxia is a critical environmental factor that doubles the number of VE‐cadherin+/CD31+ at the end of 7 days and produces arterial endothelial cells with great therapeutic potential. We determined hypoxia regulates both differentiation of ESCs to endothelial cells and their regenerative function. Initial hypoxic exposure, 1% O2, committed ESCs to endothelial lineage by upregulating the transcription factor Etv2 fivefold via Hif1α. Subsequently, prolonged hypoxia induced Notch signaling also via Hif1α, which specified arterial identity, marked by the increased expression of the arterial specific markers, Ephb2, Notch1, and Dll4. Transplantation of endothelial cells in myocardial infarction and hind limb models demonstrated hypoxia derived arterial endothelial cells conferred long‐term benefit and restored vascularity better than normoxia derived endothelial cells. Based on these findings, Hif1α plays a dual role in first specifying endothelial lineage via upregulation Etv2, and thereafter specifying for arterial lineage through Notch activation. Furthermore, hypoxia derived arterial endothelial cells are superior to normoxia derived endothelial cells in treating ischemic tissue.

Support or Funding Information

NIH Lung and Pathobiology Training Program: NIHT32HL007829‐22
Structural Analysis of the 26S Proteasome Complex to Understand Its Function and Regulation
Authors: Huang Lan
Published: November 2023

The ubiquitin‐proteasome system (UPS) represents the major pathway for regulated degradation of intracellular proteins in eukaryotes, which plays an important role in regulating many biological processes such as cell cycle progression, signal transduction and DNA repair. The 26S proteasome is the macromolecular machine responsible for ATP/ubiquitin dependent degradation, and is composed of at least 33 subunits that form two subcomplexes, 20S core particle and 19S regulatory particle. Disruption of proteasomal degradation has been implicated in many human diseases, and components in the UPS have become attractive therapeutic targets in recent years. Therefore, structural analysis of the human 26S proteasome complex will not only advance our understanding of its action and regulation mechanisms, but also will uncover potential targets for future cancer therapeutics. However, characterization of the 26S proteasome complex using conventional structural tools has been an extremely challenging task due to its dynamics and heterogeneity. Recently, cross‐linking mass spectrometry (XL‐MS) has emerged as a powerful and alternative structural tool to for studying protein‐protein interactions and elucidating architectures of protein complexes. In addition to capture protein‐protein interactions in cells, XL‐MS experiments allow the identification of cross‐linked peptides and define protein physical contacts at the amino‐acid level resolution. The information obtained can be used to derive protein interaction network topology and structural models of protein complexes. Although effective, XL‐MS studies have several inherent limitations. Here we present a novel cross‐linking mass spectrometry (XL‐MS) strategy based on our newly developed MS‐cleavable cross‐linking reagents and multistage tandem mass spectrometry to define protein‐protein interactions of the human 26S proteasome, especially as they occur in living cells. With this new approach, we have determined structural dynamics of the 26S proteasome and identified cross‐links between proteasome subunits and their interacting proteins. Our results have provided structural details on how protein‐protein interactions are involved in modulating proteasomal functions. The methodology presented here can be adopted for the study of other protein complexes in vitro and in vivo.

Support or Funding Information

This work is supported by NIH RO1GM074830 to L.H, and R01GM106003 to L.H. and S. R..
Effective Transfer of Nutritional Messages to Caregivers by Health Service Providers Trained in Counseling in Two Poor Districts of the Lambayeque Region, Peru
Authors: Charron Myriam B. , Marquis Grace S. , Creed‐Kanashiro Hilary M. , Martinez Rosario Bartolini , Sernaqué Cindy Castro
Published: November 2023

Suboptimal infant and young child feeding practices contribute to poor nutrition outcomes. The 2015 Peru Demographic Health Survey reported that 49% of infants 6–8 months did not consume meats, poultry, fish, or eggs and 36% received fewer than three food categories. These inadequate feeding practices contribute to the high rates of anemia (43.5% of children 6 – 35 months). In response, the Lambayeque regional government funded a train‐the‐trainer initiative in the four poorest districts of the region to improve the skills of health service professionals (HP) in effective nutrition education counselling. The objectives of the present study were to evaluate how the training was currently applied in counselling by HP and to identify influential factors on effective transfer of improved nutrition practices to caregivers. Of particular interest was to examine interpersonal relationships between HP and caregivers.

Data were collected in six health establishments in two of the four selected Lambayeque districts. We completed in‐depth interviews with 5 HP, and 34 exit interviews with caregivers, of whom 7 gave in‐depth interviews and 5 who also permitted home observations. In addition, 29 direct participant observations of visits to the child growth and development monitoring program were conducted to observe the counselling.

Counselling messages focused on how to use multi‐micronutrient powders and increase consumption of iron‐rich foods (e.g., liver, sangrecita). A majority of caregivers identified those same messages as the most important ones to assure their children's health. Interviews with caregivers and home observations indicated that nutritional messages (e.g., give more iron‐rich foods, give more legumes) were acceptable and feasible to achieve in the household. Learning materials (e.g., model plates) and group demonstration sessions facilitated caregiver comprehension, whereas caregivers' Quechua language was a barrier. Challenges that affected the continuity of good counselling in the health services were the frequent rotation of health service personnel and poor caregiver attendance. Lastly, beliefs or traditions prevented the adoption of some messages (e.g., duck is a cold meat, consuming animal blood (sangrecita) is comparable to consuming the animal's soul).

Health professionals in the targeted districts used counselling skills demonstrated in the on‐going training and delivered the training's key nutrition messages. The HP made use of learning materials and used different delivery methods; caregivers understood the nutritional messages and applied them in their home. To conclude, HP also benefited from this on‐going initiative as they manifested a sense of satisfaction in what they had accomplished in improving children's health and nutritional status.

Support or Funding Information

McBurney Foundation
A novel FADS2 isoform isolated from milk fat globules suppresses FADS2 mediated Δ6‐desaturation of omega‐3 fatty acids
Authors: Kothapalli Kumar , Park Hui Gyu , Guo Xiaoxian , Sun Xuepeng , Zou James , Hyon Stephanie S , Qin Xia , Lawrence Peter , Ran‐Ressler Rinat R , Zhang Ji Yao , Gu Zhenglong , Brenna James Thomas
Published: November 2023

Introduction

Alternative mRNA splicing is increasingly recognized as a modulator of protein structure and function. Here we report identification of a novel alternative transcript of fatty acid desaturase 2 (FADS2) and characterization of its function, discovered during the study of alternative transcripts in human milkfat globules (MFG).

Methods

Human breastmilk collected from a single donor was used to isolate MFG. The isolated MFG was used to extract total RNA and construction of mRNA‐sequencing library. The constructed library was sequenced using an Illumina HiSeq instrument operating in high output mode. Expression levels of evolutionary conserved FADSAT were measured using cDNA from MFG by semi‐quantitative RT‐PCR assay.

Results

A total of 52 million reads were sequenced, showing expression of 15605 transcripts. Classical fatty acid desaturase 2 (FADS2), which catalyzes the rate limiting step in PUFA synthesis, is moderately expressed. A novel FADS2 alternative transcript (FADS2AT2) with 386 amino acids was identified. When FADS2AT2 was transiently transfected to stable FADS2 MCF7 cells and incubated with omega‐3 fatty acid precursor 18:3n‐3, suppression of delta 6 desaturation (D6D) product 18:4n‐3 and its downstream 20:4n‐3 and 20:5n‐3 fatty acids were observed compared to control cells. No significant changes were observed when incubated with omega‐6 fatty acid precursor 18:2n‐6. FADS2, FADS2AT1 and 5 out of 8 known FADS3AT were expressed in MFG. FADS1, FADS3AT3, and FADS3AT5 are undetectable.

Conclusion

FADS2AT2 regulates noncatalytically classical FADS2 mediated Δ6‐desaturation of n‐3 but not n‐6 PUFA biosynthesis. This novel spliced isoform mediated interaction is the first molecular mechanism by which desaturation of one PUFA family but not the other is modulated.

Support or Funding Information

AT007003
If a picture already tells a thousand words, how many more do we need to add?
Authors: Bretschneider Jochen , Rothman Zachary
Published: November 2023

We review the unique opportunities that video production provides for teaching and learning, with a focus on storytelling using sounds, images, and yes, even (occasionally) words.

Subject Matter Expertise is rooted in the written word and the public presentation, but contemporary tools and new methods of distribution require educators and experts to learn a new kind of media literacy.

Innovate or perish. Communicate or disappear.

We take the audience on a journey from written word to motion picture, using examples of our past video productions ‐ from the high production value 4K UBC Neuroanatomy Series to shorter, cost effective, more focused lessons on human anatomy shot with a smartphone. We show that video production is not only a necessary piece of the new learning ecosystem, but one that you can engage with directly using tools you might already have in your pocket. Engaging and thought provoking, this hands‐on session will create a small army of fledgling filmmakers.

Support or Funding Information

None
Maternal Hypercholesterolemia and Phytosterol Intervention on Oxysterol Concentrations in Newly‐Weaned ApoE Deficient Mice
Authors: Dumolt Jerad , Radhakrishnan Sandhya , Mathew Joyce , Patel Mulchand , Browne Richard , Rideout Todd
Published: November 2023

During hypercholesterolemic pregnancies, the fetus is exposed to excessive cholesterol that is thought to increase cardiovascular disease risk in adults. We recently reported that newly‐weaned offspring from hypercholesterolemic apoE−/− mice have increased blood lipid concentrations that are normalized by maternal phytosterol (PS) supplementation throughout gestation and lactation. However, the influence of maternal hypercholesterolemia and PS supplementation on offspring oxysterols, bioactive oxygenated cholesterol derivatives that regulate arterial health and lesion progression, have yet to be addressed. Therefore, we tested the hypothesis that offspring born to hypercholesterolemic mothers would have increased circulating oxysterol concentrations and that pups from PS‐supplemented mothers would have a more favorable serum and hepatic oxysterol profile compared with pups from unsupplemented mothers. Twenty‐one female apoE−/− mice were randomly assigned to three different chow based diets throughout gestation and lactation: chow (chow; control), chow diet with high cholesterol (CH; 0.15% (w/w), and chow diet with 0.15% (w/w) cholesterol and 2% (w/w) phytosterol (CH/PS). On postnatal day 21, offspring were euthanized for serum and hepatic oxysterol profiling and transcriptional changes in hepatic sterol regulatory targets by HPLC and RT‐PCR, respectively. Pups born to hypercholesterolemic mothers had increased (p<0.05) serum cholesterol, 25‐hydroxycholesterol (HC), 7αHC, 7βHC, and 7‐ketocholesterol that were normalized by maternal PS‐supplementation. Hepatic mRNA expression of 7α‐hydroxylase (CYP7A1) was increased (p<0.05) in pups born to hypercholesterolemic mothers but normalized in pups from PS‐supplemented mothers. Compared with the CH group, pups from PS‐supplemented mothers demonstrated increased transcription of liver X receptor (LXR) and its target gene adenosine triphosphate binding cassette G8 (ABCG8). No difference (p>0.05) in the transcription of hepatic oxysterol binding proteins (OSBP 3, 8, and 7) was observed between the groups. These results suggest that, beyond increased circulating cholesterol, newly‐weaned offspring from hypercholesterolemic mothers have enhanced serum oxysterol concentrations and that maternal PS supplementation attenuates this response.

Support or Funding Information

Supported by the National Institute for Complementary and Alternative Medicine.
Quantitation of Trans‐Fatty Acids in Human Plasma from the National Health and Nutrition Examination Survey
Authors: Kuiper Heather C , Caudill Samuel P , Vesper Hubert W
Published: November 2023

Trans‐fatty acids (TFA) are geometric isomers of naturally occurring cis‐fatty acids, formed industrially via partial hydrogenation of vegetable oils or naturally in ruminant animals. High dietary TFA intake results in increased low density lipoprotein cholesterol levels and has been associated with other risk factors for cardiovascular disease. Due to these adverse health effects, reduction of TFA consumption is a major public health objective. Food intake studies have provided estimates for TFA levels in the U.S. population; however, there is a need for nationally representative data on TFA levels in blood.

We developed and validated a new isotope dilution‐gaschromatography‐negative chemical ionization‐mass spectrometry (ID‐GC‐NCI‐MS)method for the quantitation of 27 FA including four major TFA in 100 μl of human plasma at levels as low as 0.02 μM. FA were derivatized with pentafluorobenzyl‐bromide and analyzed on a 7890/5975C GC/MSD from Agilent Technologies in selected ion monitoring mode using NCI with methane as there agent gas. Separation was carried out on an Agilent Select FAME 200m × 250μmx 0.25μm column with hydrogen as the carrier gas. The limits of detection were 0.07 μM for palmitelaidic acid, 0.28 μM for elaidic acid, 0.43 μM for trans‐vaccenic acid, and 0.02 μM for linoelaidic acid. The intraday and inter‐day percent coefficients of variation for the TFA ranged from 1–11%CV and 6–15%CV respectively. The mean accuracy for all four TFA was 102% (95%CI:98%–107%).

We used this method to quantitate four major TFA, palmitelaidic acid, elaidic acid, trans‐vaccenic acid, and linoelaidic acid, in a nationally representative group of fasted adults in the U.S. population using National Health and Nutrition Examination Survey (NHANES) samples. The TFA were measured in 1613 participants from NHANES 1999–2000 and 2462 participants from NHANES2009–2010, and were detected in all samples. Geometric means for the sum of the 4 TFAs were 80.9 μmol/l (95% CI: 75.7,86.5 μmol/L) and 37.4 μmol/l (95% CI: 36.1, 38.8 μmol/L) in the NHANES 1999–2000 and 2009–2010, respectively. Overall TFA concentrations were 50% lower in NHANES 2009–2010 compared to 1999–2000.

We developed a new highly specific, high resolution ID‐GC‐NCI‐MS method to quantitate TFA and regular FA in humans in large population studies. We used this method to determine TFA levels in fasted adults in the U.S. population from NHANES 1999–2000 and 2009–2010, finding an overall reduction of TFA levels.

Support or Funding Information

None
Almond fatty acid bioavailability in hyperlipidemia: A randomized controlled crossover trial
Authors: Nishi Stephanie K , Kendall Cyril WC , Bazinet Richard P , Jenkins David JA , Sievenpiper John L
Published: November 2023

Objective

Almond intake is associated with reduced coronary heart disease (CHD) risk, yet concern remains that weight gain may occur due to their high fat content and subsequent energy density. Our aim was to assess fatty acid bioavailability of almond intake, using linoleic acid (18:2n‐6) as a marker of fat absorption, in individuals with hyperlipidemia as part of a secondary analysis of a randomized controlled clinical trial.

Methods

In a randomized crossover study, 27 hyperlipidemic men and women incorporated 3 isoenergetic (mean 423 kcal/d) supplements into a NCEP Step 2 diet each for 1 month. Supplements provided 22.2% of energy and consisted of full‐dose almonds (73±3 g/d), half‐dose almonds plus half‐dose muffins, and full‐dose muffins (control), matched for linoleic acid content. Fecal samples were collected at the end of each treatment period. Fatty acids were measured in the dietary supplements and freeze‐dried fecal samples using gas chromatography.

Results

Twenty‐two participants had fecal fatty acid data available from all 3 dietary phases for analyses. In the control supplement, linoleic acid comprised of 5.4 mg/g (536 mg/d), comparable to the linoleic acid content of the almond supplement of 5.7 mg/g (428 mg/d). There was a significantly greater amount of fecal linoleic acid following almond intake (7201±1147 mg/d) compared with the control (1802±1102 mg/d), adjusted for linoleic intake (P<0.01). For every half dose increase in almond intake (i.e. approximately 37.5 g almonds/day) there was a 2693 mg/day increase in linoleic acid excreted in the feces (P‐trend = 0.0024).

Conclusions

A dose‐response was observed with increasing linoleic acid excretion with increased almond intake. The fat content of almonds may not be as bioavailable as predicted by Atwater factors as suggested by the increased linoleic acid excretion with almond intake compared to the control. With less fat being bioavailable, meaning less kilocalories may be absorbed by the body, the concern of the ‘high energy density’ of almonds and risk of weight gain may be overstated.

Protocol registration: clinicaltrials.gov identifier, [NCT00507520]

Support or Funding Information

Source of Research Support: Almond Board of California; PSI Foundation; Banting and Best Diabetes Centre; Canadian Diabetes Association
Sex‐Specific Temporal Differences in Glucose Homeostasis in CD‐1 Mice Fed Diets with Distinct Fatty Acid Profiles
Authors: Unger Allison L , Jetton Thomas L , Kraft Jana
Published: November 2023

Sexual dimorphism in energy metabolism and glucose homeostasis is well documented. The extent to which specific nutrients differentially impact the sexes is less clear. We examined the sex‐specific effects of dietary fat type on somatic growth and metabolic responses over 9 months. Sixty male and female outbred CD‐1 mice (n = 10/group) were fed isoenergetic high‐fat diets (40% kcal fat) containing either (1) 100% American diet fat (Control, CON group, reflecting the average fatty acid profile consumed in the United States that has been linked to dysmetabolism, increased inflammation, and type 2 diabetes), (2) 70% CON fat + 30% butter oil (BO group), and (3) 70% CON fat + 30% fish oil (FO group) for 9 months. Standard physiological measurements and glucose homeostatic assays (i.e., intraperitoneal insulin and glucose tolerance tests, ITT and GTT, respectively) were performed at regular intervals (3, 6, and 9 months). There were no differences in feed intake after 9 months among the diet groups in males and females. The BO diet, however, resulted in a higher weight gain in both male and female mice compared to their respective CON group. Fed blood glucose levels did not differ among the diet groups in both sexes at 3 and 6 months, but by 9 months, both male and female FO mice tended to have the lowest blood glucose concentrations compared to CON mice (P=0.067). GTT demonstrated that in both sexes at 3 months, the BO groups exhibited reduced glucose tolerance compared to their CON groups (P<0.05) but by 6 months there were no longer differences among the diet groups. Furthermore, ITT showed that male mice exhibited reduced insulin sensitivity in the BO group compared to the CON group at 3 months (P<0.05), whereas female BO mice displayed a greater insulin sensitivity compared to the FO group (P<0.05). By 6 months, there were no differences in insulin sensitivity between the female diet groups, while male mice fed FO showed enhanced insulin sensitivity compared to the CON and BO groups (P<0.05). By 9 months, male and female BO mice had reduced insulin sensitivity compared to the FO mice (P<0.05). While the FO diet generally improved metabolic outcomes in both sexes, from the outset, the BO diet led to higher weight gain and worsened glucose tolerance and insulin resistance by the end of the study. Nonetheless, at the 3‐month time‐point, male and female mice on the BO diet exhibited transiently disparate responses to ITT. Hence, in the backdrop of a diet rich in American diet fats, dairy‐ vs. marine‐derived lipids impact metabolic outcomes in a temporally distinct, sex‐specific manner.
The impact of soaring food prices on obesity in women: A longitudinal analysis in 31 developing countries
Authors: Conklin Annalijn I. , Daoud Adel , Shimkhada Riti , Ponce Ninez
Published: November 2023

Objectives

To examine the association between food price inflation and obesity among women in low and middle‐income countries, and assess whether the association differs by socioeconomic status.

Methods

Longitudinal study of the international prices of food (FAO food price index), which measures the monthly change in prices of a basket of food commodities, temporally and geographically linked to 295,984 non‐pregnant adult (age>=24 y) women participants in the Demographic and Health Survey (DHS) from 31 low‐ and middle‐income countries (2000–2014). Multilevel logistic regression with two‐level random‐intercept growth models was used to estimate the joint association of food price inflation and SES differences with obesity, conditioning on known confounders. Post‐estimation computed population averaged differences in the predicted probability of being obese across the range of food price inflation values.

Results

We found that rising food prices were strongly associated with obesity prevalence, and particularly that the relationship showed clear differences by individual socioeconomic status (SES), regardless of the SES indicator used (Figs 1–5). The strongest disparities in the predicted mean obesity level were seen in education at the highest levels of food price inflation. On average, for every 1‐unit increase in food price inflation, women in the top SES categories had between 0.02 and 0.06 percentage point greater predicted obesity prevalence, compared to women in the bottom SES categories.

Conclusion

There is robust effect modification by socioeconomic status of the association between food price inflation and obesity in adult women in developing countries. Greater food price inflation was associated with higher levels of obesity in women in the top SES groups, who may be net food consumers most at risk of obesity in developing countries.

Support or Funding Information

This work was supported by the Canadian Institute for Health Research Postdoctoral Fellowship Award (MFE‐135520). No sponsors participated in the study design, data analysis or interpretation of results.
Characterization of Wild Blueberry Polyphenols Bioavailability and Kinetic Profile over 24‐hour Period in Human Subjects
Authors: Zhong Siqiong , Sandhu Amandeep , Edirisinghe Indika , Freeman Britt Burton
Published: November 2023

Diets abundant in phenolic compounds have been linked to decreased risk of cardiovascular disease, obesity and diabetes. Wild blueberries (WBB) are one of the richest sources of dietary phenolic compounds containing notable amounts of compounds like anthocyanins and chlorogenic acids (CGA). Understanding their metabolic fate may provide insight to their health benefits and protection against chronic disease development. The purpose of this study was to identify and assess bioavailability and biotransformation of WBB anthocyanin and CGA in human plasma over 24 h. Healthy male and female volunteers (n=12) ingested a WBB drink (25 g freeze dried WBB powder) or Control drink with a standard polyphenol free breakfast on 2 separate occasions at least 1 week apart. Blood was collected and plasma extracted at baseline (t=0h), 0.25h, 0.5h, 1h, 2h, 4h, 6h, 8h, 10h and 24h. The anthocyanins in the WBB drink and their metabolites in human plasma were identified using HPLC‐ESI‐Q‐TOF and quantified by dynamic MRM transitions on HPLC‐ESI‐QQQ. A total of 30 anthocyanins were identified in the WBB drink. These included glycosides of cyanidin, delphinidin, malvidin, petunidin and peonidin. 3‐CGA was also detected and confirmed with standards. All the anthocyanins in the WBB drink were found in plasma as well as 3‐CGA. The bioavailability for delphinidin, cyandin, malvidin, peonidin, and petunidin were each less than 1% and total bioavailability of WBB anthocyanins was 1.09%. The bioavailability for 3‐CGA was 0.22% after consuming the WBB drink. The Tmax of anthocyanins and 3‐CGA was ~2 h post ingestion. Tmax of phase II metabolites, including petunidin glucuronide, peonidin glucuronide, delphinidin glucuronide and cyanidin glucuronide was ~ 8.8, 2.6, 6.3 and 7 h, respectively. Phenolic acids metabolites, including vanillic acids, ferulic acids, 2,3‐dihydroxybenzoic acid, phloroglucinaldehyde, syringic acid were also detected in human plasma during the 24 h period. These results suggest that anthocyanins and CGAs from a WBB drink can be partly absorbed in their intact form and partly transformed to conjugated and degraded metabolites in humans. The data also indicate that there are early phase and late phase appearing metabolites in the blood of humans, which could have important health promoting implications. Future studies will be required to determine how these pools of metabolites impact physiology and the most sensitive systems to their effect.

Support or Funding Information

This study was funded by the Wild Blueberry Association of North America. Chemical analysis of clinical samples were conducted at the Institute for Food Safety and Health (Bedford Park, IL, USA). Agilent Technologies, USA, provided instruments, columns and technical services.
Goal Setting, Past Performance and Behavioral Outcomes in a Worksite Wellness Program
Authors: Jarvandi Soghra , Yates Derrick , Donaldson Joseph
Published: November 2023

We examined the Walk Across TN (WAT) program, offered as a worksite wellness program for University of Tennessee (UT) Extension and Tennessee State University (TSU) Extension employees. WAT is an eight‐week virtual walk across the state, wherein participants form teams of six persons and log their physical activity as miles of walking. The objective of this study was to examine the association between goal setting, past performance in terms of physical activity level, and physical activity outcome during the first four weeks of the program. Participants were recruited from individuals who were registered in the WAT program. Physical activity level was assessed by the International Physical Activity Questionnaire, and categorized as compliers (moderate/high level), and non‐compliers (low level). Participants set their physical activity goal, at baseline, and reported their physical activity on a weekly basis, during the program. Accordingly, we calculated the percentage of the goal achieved during the program. Regression analyses were used to examine the association between weekly physical activity level, self‐set goal and past performance. Models were controlled for age and education. A total of 52 employees (90% female) participated in this study. At baseline, 25 individuals (48%) reported a low level of physical activity, i.e., non‐compliers. During the program, the reported physical activity level, as % of the baseline goal, ranged from −45% to 347% (median = 73%), with no significant difference between compilers and non‐compliers; mean (95% Confidence Interval): 66% (−7%, 140%) vs. 101% (32%, 169%), respectively, p = 0.15. In addition, participants who were compliant with physical activity guidelines at baseline vs. non‐compliers did not differ significantly in terms of the average weekly physical activity level; least‐squares mean (standard error): 18 (4.9) vs. 14 (4.5), p = 0.16. In conclusion, participants with low level of physical activity may benefit from behavioral strategies that improve their motivation, such as group support and goal setting.

Support or Funding Information

University of Tennessee Extension, Department of Family and Consumer Sciences
Diet‐dependent Plasticity of Changes in Neural Structure and Behavior
Authors: Sawin Emily A , Gonzalez Jose G , Ong Irene M , McIlwain Sean J , Adluru Nagesh , Alexander Andrew L , Yu John‐Paul J
Published: November 2023

Background

Dietary macronutrient composition influences gut microbiome populations and these resultant microbiome populations influence diffusion tensor measures of neural structure and white matter microstructural integrity as assessed by diffusion tensor imaging (DTI).

Objective

To determine the plasticity of the changes in neural structure and white matter microstructural integrity as previously altered of diet and gut microbiome populations.

Methods

Weanling male Sprague Dawley rats were randomized to one of four diets, a control diet, a high fat diet, a high fiber diet, or a high protein‐low carbohydrate diet and fed for three weeks and then crossed over to the control diet and fed for an additional 3 weeks. Behavior was assessed using an open field maze and a Y‐maze after the first 3 weeks of feeding and then again at the culmination of the study. Neural structure and white matter integrity were assessed by DTI and global transcriptomic changes were assessed with whole transcriptome shotgun sequencing (RNA‐Seq).

Results

Diffusion tensor imaging demonstrated diet‐dependent alterations in neural structure, organization, and white matter integrity. Significant transcriptomic changes are observed when experimental diets are compared to the control diet.

Conclusion

Diet‐dependent macronutrient composition and corresponding changes in the gut microbiome can influence neural structure and white matter integrity and demonstrates surprising markers of structural, behavioral, and transcriptomic plasticity.
Metabolic Profile of Osteosarcopenic Obesity Syndrome: Identifying Biomarkers for Diagnostic Criteria
Authors: JafariNasabian Pegah , Inglis Julia E , Ave Miranda P , Hall Katie J , Nieto Sara E , Kelly Owen J , Ilich Jasminka Z
Published: November 2023

Osteosarcopenic obesity (OSO) is a recently identified geriatric syndrome characterized by the concurrent presence of osteopenia/osteoporosis, sarcopenia, and increased adiposity, the latter either as overt overweight or fat redistribution/infiltration into bone and muscle tissues. The diagnostic criteria for OSO are just being established, but there are no data on biomarkers that might characterize this syndrome. Our objective was to examine possible biomarkers associated with OSO syndrome, including serum sclerostin (as a hinder of bone formation via osteoblast inhibition) and skeletal muscle‐specific troponin T (sTnT) (as an indicator of muscle turnover/damage). A total of n=59 healthy Caucasian women ≥65 years were classified into 4 groups based on their bone and body composition profile identified by DXA measurements: 1) Osteopenic/osteoporotic non‐obese with T‐scores of L1–L4 and/or total femur ≤‐1 (N=4); 2) Obese‐only with body fat percentage ≥32 (N=10); 3) Osteopenic/osteoporotic obese (N=35); 4) Osteosarcopenic obese (OSO) (N=10). Sarcopenia was determined from the appendicular lean mass normalized by height and body fat, with the cutoff determined from negative residuals. Serum samples were analyzed using the commercial ELISA kits. Data were evaluated by Pearson's correlations and ANOVA followed by Tukey's tests with p≤0.05. Serum sclerostin concentration ranged from 0.03 to 2.49 ng/mL and was significantly higher in OSO and osteopenic/osteoporotic obese group (1.1 ± 0.2 and 1.09 ± 0.2 ng/mL, respectively) compared to the obese‐only group. The sTnT concentration ranged from 0.02 to 12.06 pg/mL and was also significantly higher in OSO group (3.2 ± 2.9 pg/mL) compared to osteopenic/osteoporotic obese and obese‐only group (1.1 ± 2.2 and 0.6 ± 0.7 pg/mL, respectively). Sclerostin was negatively correlated with bone mineral density/content (BMD/BMC) of all skeletal sites, and the relationship was statistically significant with femoral neck BMD/BMC. Moreover, there was a significant positive correlation between serum sclerostin and sTnT (r=0.3; p≤0.05), indicating their simultaneous mediation in bone and muscle loss. In conclusion, the combination of high sclerostin and sTnT can be used to better identify the metabolic profile of OSO syndrome and possibly apply as measurements for its diagnostic criteria.