bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Choreography Of An Antibiotic Assembly Line
Authors: Dutta Somnath , Whicher Jonathan R. , Hansen Douglas A. , Hale Wendi A. , Chemler Joseph A. , Congdon Grady R. , Narayan Alison R. , Håkansson Kristina , Sherman David H. , Smith Janet L. , Skiniotis Georgios
Published: November 2023

Plants and microorganisms produce a vast array of structurally complex and diverse antibacterial, antiviral, antitumor and antimetabolite substances with wide‐ranging human and animal health applications. In fact the majority of compounds used clinically and agriculturally in the United States are either natural products or semi‐synthetic derivatives thereof. Polyketides are an important class of natural compounds that often constitute the core structures or complete chemical entities for many clinically approved therapeutic agents. Their biosynthetic machinery, represented by type I polyketide synthases, has an architecture in which successive modules catalyze two‐carbon linear extensions and keto group processing reactions on intermediates covalently tethered to carrier domains. We recently employed cryo‐electron microscopy (cryo‐EM) to visualize a full‐length module from the biosynthetic pathway that creates the antibiotic pikromycin. The cryo‐EM 3D reconstructions revealed a totally unexpected architecture compared to the homologous dimeric mammalian fatty acid synthase. The dimeric PKS module creates a single reaction chamber for the two acyl carrier protein (ACP) domains that carry building blocks and intermediates between acyltransferase (AT), ketosynthase (KS), and ketoreductase (KR) active sites. By trapping the PKS module in each of several biochemical states we obtained 3D maps that recapitulate its full enzymatic cycle. The ACP domains are differentially and precisely positioned after polyketide chain substrate loading on the active site of KS, after extension to the b‐keto‐intermediate, and after b‐hydroxy product generation. The structures reveal the ACP dynamics for sequential binding to catalytic domains within the reaction chamber, and for transferring the elongated and processed polyketide substrate to the next module in the PKS pathway. This study highlights the conformational transitions coupled to substrate transfer and modification in a way that facilitates high throughput unidirectional substrate processing, and establishes a new model for molecular dissection of these multifunctional enzyme systems.
Insights On Mammalian Glycosylation Enzymes From High‐Throughput Expression Studies
Authors: Moremen Kelley , Meng L , Forouhar F. , Wang S. , Kadirvelraj R. , Moniz H. , Ramiah A. , Gao Z. , Seetharaman J. , Milaninia S. , Galay G. , Stuart M. , Steel J. , Labaer J. , Wood Z. , Tong L. , Jarvis D.
Published: November 2023

Glycan structures on cell surface and secreted glycoproteins play critical roles in biological recognition and targeting events in animal systems. The enzymes that synthesize these structures reside in membranes of the secretory pathway and modify glycoproteins in transit to the cell surface. These enzymes are generally poorly understood largely because they are challenging targets for functional expression even in eukaryotic hosts. We have established library of expression constructs encoding all human glycosylation enzymes (target gene list of ~350 coding regions) as secreted catalytic domain fusion proteins for recombinant production in HEK293 cells and baculovirus‐infected insect cells. Comparison of expression levels in each host system indicates similar trends where most proteins are well‐expressed, but only a subset are efficiently secreted. This presentation will summarize our strategies for expression and downstream workflows for biochemical and structural studies. Discussion of resulting structures and insights into catalytic mechanisms and substrate recognition will focus on recently determined structures of sialyltransferases and fucosyltransferases coming from the mammalian expression platform.

Support or Funding Information

(supported by NIH grants P41GM103390 and P01GM107012).
Mechanistic and structural insights into a human carbohydrate degrading enzyme
Authors: Gloster Tracey , Alteen Matthew , Oehler Verena , Yang Lei , Wilson Iain , Vocadlo David
Published: November 2023

Mammalian β‐hexosaminidases have emerged as playing essential roles in cellular physiology and disease. These enzymes are responsible for the cleavage of the monosaccharides N‐acetylglucosamine (GlcNAc) and N‐acetylgalactosamine (GalNAc) from cellular substrates. One of these β‐hexosaminidases, Hexosaminidase D (HexD), encoded by the HEXDC gene, has received little attention. No mechanistic studies have focused on the role of this nucleocytoplasmically localized β‐hexosaminidase and its cellular function remains unknown. We will discuss a series of kinetic, mechanistic and structural investigations into HexD that have aided defining the precise catalytic mechanism of this enzyme. The fundamental insights gained from these studies will aid in the development of potent and selective probes for HexD, which will serve as useful tools to better understand the physiological role played by this enzyme.

Support or Funding Information

T.M.G. and V.O. are supported by a Wellcome Trust Career Development Fellowship. D.J.V. thanks the Canada Research Chair program for support as a Canada Research Chair in Chemical Glycobiology. M.A. thanks the NSERC CREATE Collaborative Medicinal Chemistry Network in Epigenetics Training (ChemNET) for support. This work was supported by an NSERC Discovery and a CIHR Operating grant (MOP‐123341). I.N. was recipient of an “Aktion Austria‐Slovakia” scholarship from the Österreichischer Austauschdienst.
Impeding the formation of Transcription Initiation complex
Authors: Egly Jean‐Marc
Published: November 2023

RNA synthesis is the result of a cascade of chronologically orchestrated events that requires several hundreds of proteins including RNA polymerase II, the general transcription factors, mediator, co‐activators, co‐repressors and chromatin remodelers are assembled around the promoter. Among these proteins necessary to initiate RNA synthesis, we recently identified the Nucleotide‐Excision‐Repair (NER) factors demonstrating their dual role in transcription and DNA repair. Mediator occupies a key role in protein coding genes expression in mediating the contacts between gene specific factors and the basal transcription machinery.

Mutations in one of these factors results in rare genetic disorders: Xeroderma Pigmentosum (XP), Trichothiodystrophy (TTD), Cockayne Syndrome (CS), for TFIIH and NER factors; non‐syndromic mental retardation, Charcot‐Marie Tooth, Opitz‐Kaveggia … for Mediator.

We show how each of the mutations in either NER factors or Mediator subunits specifically disturbs the protein/protein interactions network required for the accurate formation of the transcription complex at the promoter of activated genes.

The NER proteins seem to be necessary at the promoter of activated genes in order to achieve an optimal 3D loop structure that requires DNA demethylation, formation of DNA cuts as well as histone posttranslational modifications. We also show how the Mediator mutations cause distinct expression of Immediate Early Genes (IEG) with as a consequence disruption of later genes expression.

Our study shed light on the molecular mechanism underlying gene expression regulation at the transcription initiation level explaining at least partially some of the clinical features of the above‐mentioned genetic disorders.
ELONGIN AND THE ELONGIN A UBIQUITIN LIGASE COMPLEX IN TRANSCRIPTION AND THE RESPONSE TO DNA DAMAGE
Authors: Conaway Joan W , Weems Juston C. , Slaughter Brian D. , Unruh Jay R. , Conaway Ronald C.
Published: November 2023

Elongin A performs dual functions in cells as a component of the Elongin ABC complex, a Pol II elongation factor, and as the substrate recognition subunit of an E3 ubiquitin ligase that works in concert with the ubiquitin ligase NEDD4 to target Pol II stalled at sites of DNA damage and other impediments for ubiquitination and degradation by the proteasome. Assembly of the Elongin A ubiquitin ligase proceeds via binding of the Elongin ABC complex to a heterodimer composed of Cullin family member CUL5 AND RING finger protein RBX. We recently discovered that assembly of the Elongin A ubiquitin ligase is a tightly regulated process induced by a wide variety of stimuli and signal transduction pathways. Whereas under normal conditions, the majority of Elongin A is present in cells in the Elongin ABC complex, assembly of the Elongin A ubiquitin ligase is induced by DNA damage and other stresses that lead to accumulation of stalled Pol II. Assembly of the Elongin A ubiquitin ligase is also induced by stimuli known to activate Elongin A‐dependent transcription, such as endoplasmic reticulum and nutrient stress and retinoic signaling. Furthermore, assembly of the Elongin A ubiquitin ligase can be induced by doxycycline in U2OS cells carrying multiple copies of a doxycycline‐inducible transgene, but not in parental U2OS cells, suggesting that transcription activation per se is sufficient to drive ligase assembly. These findings raise the intriguing possibility that the Elongin A ubiquitin ligase might play roles not only as part of a “fail‐safe” mechanism to remove stalled Pol II from genes, but also in normal transcription activation processes.

Support or Funding Information

This work was supported by National Institutes of Health Grant GM041628, a grant to the Stowers Institute from the Helen Nelson Medical Research Fund at the Greater Kansas City Community Foundation, and by the Stowers Institute for Medical Research.
The Cancer Cell Map Initiative
Authors: Ideker Trey
Published: November 2023

Progress in DNA sequencing has revealed the startling complexity of cancer genomes, which typically carry thousands of somatic mutations. However, it remains unclear which are the key driver mutations or dependencies in a given cancer and how these influence pathogenesis and response to therapy. Although tumors of similar types and clinical outcomes can have patterns of mutations that are strikingly different, it is becoming apparent that these mutations recurrently hijack the same hallmark molecular pathways and networks. For this reason, it is likely that successful interpretation of cancer genomes will require comprehensive knowledge of the molecular networks under selective pressure in oncogenesis. I will discuss the creation of a new effort, The Cancer Cell Map Initiative (CCMI), aimed at systematically detailing these complex interactions among cancer genes and how they differ between diseased and healthy states. I will present recent progress that enables creation of these cancer cell maps across a range of tumor types and how they can be used to target networks disrupted in individual patients, significantly accelerating the development of precision medicine.
Integrative Pathway Mapping
Authors: Sali Andrej
Published: November 2023

The networks and spatial structures of biomolecular interactions provide insights into their function and thus help us to understand the workings of living cells. Detailed structural characterization of large and often dynamic assemblies and their networks is generally impossible by any single existing experimental or computational method. This challenge can be overcome by hybrid approaches that integrate data from diverse biophysical experiments (eg, X‐ray crystallography, NMR spectroscopy, electron microscopy, chemical cross‐linking, yeast‐two hybrid system, and various chemical genetics and proteomics approaches). We formulate the hybrid approach to structure and/or network determination as an optimization problem, the solution of which requires three main components: the representation of the assembly or network, the scoring function, and the optimization method. The ensemble of solutions to the optimization problem embodies the most accurate characterization given the available information. The key challenges remain translating experimental data into restraints on the structure and/or network, combining these spatial and/or network restraints into a single scoring function, optimizing the scoring function, and analyzing the resulting ensemble of solutions. The approach will be illustrated by several applications to specific biological systems, including the structure determination of the nuclear pore complex and the mapping of the gulonate pathway in Haemophilus influenzae.
A 22 bp FADS2 Insertion‐Deletion (Indel) Polymorphism Influences Arachidonic Acid Status
Authors: Kothapalli Kumar S.D , Gadgil Maithili S. , Carlson Susan E. , O'Brien Kimberly O. , Ye Kaixiong , Zhang Ji Yao , Park Hui Gyu , Ojukwu Kinsley , Zou James , Hyon Stephanie S. , Joshi Kalpana S. , Keinan Alon , Brenna J. Thomas
Published: November 2023

Introduction

The fatty acid desaturase 2 (FADS2) gene product catalyzes a key step in the biosynthesis of biologically active long chain polyunsaturated fatty acids (LCPUFA). The rs66698963 a 22 bp polymorphic insertion‐deletion (Indel) is associated with basal expression of FADS1 which mediates the Δ5‐desaturation of dihomo‐gamma‐linolenic acid to arachidonic acid (20:3n‐6→20:4n‐6), as well as coordinated induction of FADS1 and FADS2 expression in vitro. Vegans rely almost exclusively on endogenous synthesis to generate LCPUFA and we hypothesized that an adaptive genetic polymorphism would confer advantage.

Methods

A total of 234 individuals of a primarily vegetarian Indian population and 311 individuals from the U.S were genotyped. Evolutionary analysis testing for positive selection on the FADS region was performed using genetic variations data from the 1000 Genomes Project (1000GP). Functional analysis of rs66698963 genotypes and fatty acid levels was evaluated in a subset of the U.S. population.

Results

A much higher I/I genotype frequency was found in Indians (68%) than in the U.S. (18%). Data from 1000 Genomes Project confirmed our observation and revealed a global I/I genotype of 70% in South Asians, 53% in Africans, 29% in East Asians, and 17% in Europeans. Evolutionary analyses revealed for the first time signals of positive selection around rs66698963 in only South Asians. Basal plasma phospholipid arachidonic acid status was 8% greater in I/I compared to D/D individuals. The biochemical pathway product‐precursor difference, arachidonic acid minus linoleic acid, was 31% and 13% greater for I/I and I/D compared to D/D, respectively.

Conclusion

Our study is consistent with previous in vitro data suggesting that the insertion allele enhances n‐6 LCPUFA synthesis and may confer an adaptive advantage in South Asians because of the traditional plant‐based diet practice.

Support or Funding Information

R01 AT007003
Anti‐inflammatory and anti‐cancer effects of the colonic metabolites of polymethoxyflavone
Authors: Wang Minqi , Wu Xian , Song Mingyue , Xiao Hang
Published: November 2023

Polymethoxyflavones (PMFs) are unique flavonoids found in citrus fruits, and they have been shown to possess protective effects against inflammation‐associated colon carcinogenesis in mice. To further understand the molecular mechanism underlying these effects, we characterized the colonic metabolites of PMFs in mice fed with two major citrus PMFs, i.e. nobiletin (NOB) and 5‐demethoxylnobiletin (5DN) respectively (0.1% in the diet for 20 weeks). Multiple demethylated metabolites of NOB and 5DN were identified in the colonic mucosa. Interestingly, the abundance of these metabolites in the colon was much higher than that of the parent compounds. Mixture of colonic metabolites were isolated from feces, and subject to in vitro tests for anti‐inflammatory and anti‐cancer effects. It was found that the fecal isolates potently inhibited the growth of multiple human colon cancer cells, and suppressed the lipopolysaccharide‐induced inflammation in macrophages. It is noteworthy that the aforementioned biological effects of the fecal isolates were observed at the achievable levels of metabolites found in the colonic tissues of mice fed with PMFs, and these effects were hundreds folds more potent than those of the parent compounds alone. Overall, this study revealed that the colonic metabolites of PMFs, rather than the PMFs themselves, were mainly responsible for the protective effects of orally administered PMFs against inflammation and carcinogenesis in the colon.

Support or Funding Information

This study was supported by funding from NIH, AICR and USDA.
Dietary Sphingomyelin Attenuates Inflammation and Metabolic Dysfunction in Diet‐ Induced Obese Mice
Authors: Norris Gregory H , Porter Caitlin M , Jiang Christina , Blesso Christopher
Published: November 2023

Current evidence indicates that dietary sphingomyelin (SM) is lipid‐lowering and anti‐inflammatory, although its potential to prevent chronic disease as part of the diet has not been fully explored. SM is not a dietary essential and there is no recommended dietary intake. Consumption of dietary sphingolipids in Western diets is relatively common (0.3–0.4 g/day) and comes mainly from eggs and milk products. However, little is known about an optimal intake of SM and whether an increased dietary intake of SM is beneficial to health. Egg SM (ESM) and milk SM (MSM) differ in their fatty acid and sphingoid base composition, and may have different bioactivities when consumed in the diet. We evaluated the effects of milk and egg SM on diet‐induced obesity in high fat, high cholesterol diet‐fed C57BL/6J mice. We hypothesized that dietary SM would attenuate inflammation and metabolic dysfunction that occurs with obesity. We fed male C57BL/6J mice a high fat, high cholesterol diet (31% lard and 0.2% cholesterol by weight) (CTL; n = 14), or the same diet supplemented with either 0.1% (w/w) egg SM (ESM; n = 14) or 0.1% (w/w) milk SM (MSM; n = 13). After 10 weeks, ESM had gained significantly less weight than CTL reflected by a reduced epididymal adipose weight. ESM had significantly lower plasma cholesterol and fasting glucose when compared with the other groups. Although no significant difference was found in liver weight, H&E staining of both SM groups revealed an attenuation in the development of hepatic steatosis. Both SM groups had significantly lower plasma IFNγ and MCP‐1 compared to CTL. MSM also significantly lowered plasma TNFα, MIP‐1β, and IL‐6 compared to CTL. The reduction in inflammatory markers lead to an exploration of SM effects on macrophage activation. Milk SM significantly blunted LPS induction of both MCP‐1 and TNFα mRNA in RAW264.7 macrophages. These data suggest dietary SM has potential to influence obesity, through inhibiting lipid absorption and inflammation.

Support or Funding Information

Supported by the University of Connecticut
Gamma Tocotrienol Suppresses NLRP3 Inflammasome by Dual Mechanism of A20‐ mediated Priming Inhibition and AMPK/autophagy Axis Activation
Authors: Kim Yongeun , Chung Soonkyu
Published: November 2023

Nod‐like receptor 3 (NLRP3) inflammasome is the intracellular innate immunity sensor that processes and releases IL‐1β in response to microbial invasion or metabolic danger signals such as saturated fatty acids and free cholesterol. Aberrant activation of NLRP3 is intimately associated with numerous chronic inflammatory diseases. However, little information is available as to whether NLRP3 inflammasome is regulated by dietary factors. The aim of this study is to investigate whether gamma‐tocotrienol (γT3), an unsaturated form of vitamin E, downregulates NLRP3 inflammasome activation, and to determine the molecular mechanisms. Pretreatment of γT3 (0.5–10 mM) significantly suppressed activation of NLRP3 inflammasome reporter, caspase‐1 cleavage, and IL‐1β and IL‐18 secretion in J774 macrophages as well as bone marrow‐derived murine macrophages (BMDM). To further determine the mechanisms, we investigate the role of γT3 on NFκB activation and AMPK/autophagy axis activation. γT3 significantly attenuated proinflammatory gene expressions of IL‐1β, IL‐18 and NLRP3, and induced A20 expression, an ubiquitin‐editing enzyme to interrupt NFκB signaling. Induction of A20 concurred with 1) the decrease of p‐IKKα/β, p‐ERK, and p‐IκBα; 2) the reappearance of IκBα, and 3) the disappearance of TRAF6, suggesting a negative feedback of A20 on TRAF6/IKK/NF‐κB signaling. Moreover, silencing of A20 markedly dampened the inflammasome inhibitory effects of γT3. Intriguingly, γT3 treatment was also associated with AMPK/autophagy axis activation shown through LC3II accumulation and increased levels of AMPK phosphorylation. The inhibition of AMPK with Compound C completely reversed γT3's inhibitory role on NLRP3 inflammasome and caspase‐1 cleavage. Taken together, we demonstrated that γT3 suppresses NLRP3 inflammasome by two mechanisms, 1) inhibition of TRAF6/NFκB axis activation through induction of A20, and 2) activation of AMP kinase/autophagy thereby inhibiting inflammasome assembly.

Support or Funding Information

American Heart Association
Docosahexaenoic Acid Inhibits Cerulein‐Induced Cytokine Expression by Activating Peroxisome Proliferator‐Activated Receptor γ in Pancreatic Acinar Cells
Authors: Song Eun Ah , Lim Joo Weon , Kim Hyeyoung
Published: November 2023

Oxidative stress is regarded as a major pathogenic factor in acute pancreatitis. Cerulein pancreatitis is similar to human edematous pancreatitis involving dysregulation of digestive enzyme production, cytoplasmic vacuolization, and increased cytokine production. Previously, we showed that cerulein activates NADPH oxidase to produce reactive oxygens species (ROS). ROS mediate Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway and cytokine expression in pancreatic acinar cells. And agonists of peroxisome proliferator‐activated receptor γ (PPARγ) inhibit cerulein‐induced cytokine expression by regulating JAK2/STAT3 in pancreatic acinar cells. Docosahexaenoic acid (DHA) exerts anti‐inflammatory and anti‐oxidant effect. Recently, DHA has been known to activate PPARγ in the cells. PPARs are ligand‐activated transcription factors belonging to nuclear receptor superfamily. PPARγ ligands show anti‐inflammatory activities in various cells by inhibiting the expression of pro‐inflammatory cytokines. PPARγ agonists protect the cells against oxidative stress‐mediated inflammation through reducing ROS levels by inducing antioxidant enzymes such as catalase and GSH peroxidase.

The present study is purposed to investigate whether DHA inhibits cerulein‐induced cytokine expression by activating PPARγ and inhibiting JAK2/STAT3 signaling in pancreatic acinar AR42J cells.

The cells were pre‐treated with DHA for 2h, and then stimulated with cerulein (10−8 M). In other sets of experiments, the cells were treated with PPARγ agonists (Troglitazone, 15‐Deoxy‐ Δ12,14‐prostaglandin J2) or DHA and PPARγ antagonist GW9662. The mRNA and protein levels of IL‐6 and PPARγ were determined using Real‐time PCR and Western blot analyses. ROS levels were determined using DCF‐DA.

The results showed that DHA inhibited cerulein‐induced IL‐6 expression and JAK2/STAT3 activation in AR42J cells. DHA induced the expression of PPARγ. PPARγ agonists inhibited cerulein‐induced IL‐6 expression. DHA reduces the levels of ROS and IL‐6, which was reversed by co‐treatment of PPARγ antagonist in cerulein‐stimulated AR42J cells.

In conclusion, DHA inhibits Jak2/Stat3‐mediated IL‐6 expression by activating PPARγ and reducing ROS levels in pancreatic acinar cells. DHA may be beneficial for suppressing the development of pancreatitis by inhibiting cytokine expression in pancreatic acinar cells.

Support or Funding Information

This study was supported by a grant (NRF‐2015R1A2A2A01004855) from the NRF of Korea.
Anti‐inflammatory properties of tangeretin, 5‐demethyltangeretin and their primary metabolites
Authors: Guo Shanshan , Wu Xian , Zheng Jinkai , Dong Ping , Qiu Peiju , Xiao Hang
Published: November 2023

Inflammation plays important roles in the development of multiple chronic diseases. Increased consumption of anti‐inflammatory nutraceuticals has been considered as a promising strategy to prevent inflammation‐driven diseases. Orally ingested nutraceuticals undergo complex metabolism in the body, which gives rise to various metabolites. As the results, both the parent nutraceuticals and their metabolites may contribute to the overall biological effects. Tangeretin (TAN) and 5‐demethyltangeretin (5DT) are unique flavonoids found in citrus fruits. In mice fed with TAN and 5DT, we identified the primary metabolites of TAN and 5DT as 4′‐ demethyltangeretin (4DT) and xanthomicrol (XAN), respectively. Our results showed that TAN, 5DT and their metabolites exhibited extensive anti‐inflammatory effects in lipopolysaccharide (LPS)‐stimulated RAW 264.7 macrophages. More importantly, 4DT and XAN showed stronger anti‐inflammatory effects than their parent compounds TAN and 5DT. 4DT inhibited LPS‐induced expression of iNOS and COX‐2 by modulating multiple signaling pathways, particularly by suppressing the activation of p38, JNK, and PI3K/Akt, and inhibiting nuclear translocation of NF‐κB. XAN also significantly inhibited LPS‐induced inflammation in RAW 264.7 macrophage, which was evidenced by lowered nitric oxide and PGE2 production, decreased protein levels of iNOS and COX‐2, decreased gene expression of IL‐1β, and increased expression of phase II enzyme HO‐1. Overall, our results showed that TAN and 5DT are promising dietary anti‐inflammatory agents due to the fact that their primary metabolites possess potent anti‐inflammatory activities.

Support or Funding Information

This study was supported by funding from NIH, AICR and USDA.
Effects of a higher vs. lower protein diet on weight loss in teenagers: Results from a randomized controlled trial
Authors: Apolzan John William , Hsia Daniel S , Martin Corby K
Published: November 2023

Objective

To provide pilot data on weight loss efficacy in overweight and obese adolescents during isocaloric lower vs higher protein weight loss diets utilizing the U.S. Department of Agriculture (USDA) MyPlate nutrition guide.

Methods

Thirty two, 12–17 year old adolescents with body mass index ≥ 85th percentile were recruited for a 12‐week free‐living weight loss intervention. Participants were randomized to either a lower protein group with 15% of energy as protein and 60% of energy from carbohydrate or a higher protein group with 30% of energy as protein and 45% of energy from carbohydrate. Both diets restricted energy intake by 25%. Dietary counseling was based on the USDA MyPlate guidelines. The first intervention session was individual followed by 6 (biweekly) group sessions. Participants had anthropometric measurements and performed retrospective visual analogue scale (VAS) appetite ratings at baseline and week 12.

Results

Participants were 75 % female and 62.5 % black. The baseline mean (± SD) age, body weight, and BMI z‐score were 14.3 ± 1.5 y, 96.0 ± 21.9 kg, and 2.21 ± 0.48, respectively. The lower protein group reduced BMI z‐score compared to the higher protein group (0.18 ± 0.16 vs. 0.05 ± 0.09; p<0.05). No other group differences were found but fullness tended to increase in the higher protein group (0.5 ± 20.5 vs. 14.9 ± 15.2; p=0.08). Participants lost 3.1 ± 2.0 kg vs. 1.5 ± 4.2 kg body weight and 2.8 ± 2.4 % vs. 3.0 ± 5.2 % body fat in the lower vs. higher protein groups, respectively. The lower protein group change from baseline BMI z‐score, body weight, and body fat were reduced (p≤0.002) but the higher protein group change from baseline values were not different from baseline. Exploratory analyses, with the protein groups combined, indicated that overweight adolescents reduced BMI z‐score 0.38 ± 0.12 compared to 0.07 ± 0.08 in the obese subgroup (p<0.01).

Conclusions

Participants in the higher protein group tended to increase fullness, but this did not translate to greater weight loss. Higher dietary protein intake should not be recommended for weight loss in group based interventions in this study population. An adolescent intervention based on the USDA MyPlate guidelines is efficacious for weight loss in adolescents.

Support or Funding Information

NIH U54 GM104940 and NIH P30 DK072476
A Father's Response to Having a Child who is Overweight/Obese
Authors: Battisti Francis Louis , Battisti Helen E.
Published: November 2023

Study Objective

The objective of this qualitative study was to develop a theory to understand a father's response to having a child who is overweight or obese. This study was pursued for four reasons: 1) The literature is rich with studies that explore the influences of the mother/child interaction as it relates to weight. 2) Studies exploring the influences of the parent/child perspective, as they relate to weight of the child, tend to focus on maternal influences, while largely ignoring the paternal impact. 3) The limited number of father/child interaction studies suggests that researchers see this relationship as insignificant. 4) Studies that do explore the father's influence tend to look only at paternal genetic factors which contribute to the child's weight.

Statement of Methods

A Grounded Theory research design was utilized to develop a theory to understand a father's response to having a child who is overweight or obese. The fathers (n=12) were recruited from a family medical practice in Upstate New York. Using a two‐component approach, demographic information was obtained, followed by a semi‐structured individual interview to understand each father's response. All were the biological fathers and married, with two in the process of divorce. The mean age (n=10) was 42.6 years (two fathers refused to report their age). Eleven fathers were Caucasian and one was Hispanic/Latino. The mean age of the children, all of whom were >85% for weight (n=13, 77%M) was 9.6 years. One father had two children who met the research criteria.

Summary of Results

The interviews revealed the complex, multi‐dimensional nature of identifying aspects of the father's response to his child's overweight or obese status. From the interviews, six themes evolved: 1) Fathers worry about their child being overweight or obese related to psychological and physical health. 2) Fathers experience confusion as to the cause of their child being overweight. 3) Fathers minimize their impact on their child's weight and eating behaviors. 4) Fathers become overwhelmed and non‐functional when attempting to address their child's overweight or obesity. 5) Fathers defer responsibility for their child's weight to others when they don't know how to help their child manage weight. 6) Fathers engage with their child's weight issues when they can cognitively and/or emotionally understand what the child is feeling. The Theory of Interactive Factors That Lead to a Father's Response (TIF) was developed.

Conclusion Statement

Limited research regarding the father's influence on a child's weight has been conducted. With fathers making up an estimated 16% of stay‐at‐home parents, researchers are becoming increasingly interested in the role that fathers play. The TIF provides a framework that increases the understanding of motivational factors of fathers for affective and cognitive engagement.

Support or Funding Information

None
Ethnic Differences in Cumulative Exposure to Food Insecurity and Risk of Childhood Asthma
Authors: Mangini Lauren D , Dong Yongquan , Hayward Mark D , Forman Michele R
Published: November 2023

Background & Objectives

Prevalence rates of asthma have steadily risen in the U.S. and are higher in non‐Hispanic black (NHB) than in non‐Hispanic white (NHW) or Hispanic children. Likewise, NHBs are at higher risk for food insecurity than the other 2 ethnic groups. Little is known about the relationship between cumulative exposure to household food insecurity and childhood asthma. The objective was to determine the relationship between exposure to food insecurity and asthma in NHW, NHB and Hispanic school‐aged children.

Methods

Data from 4 waves of the Early Childhood Longitudinal Study‐Kindergarten cohort (ECLS‐K) were analyzed beginning in kindergarten through 8th grade (N=6,031). Food insecurity was measured with the 18‐item USDA module and at each wave of data collection, an episode is defined as household food insecurity during the prior year. Ever‐diagnosis of asthma and sociodemographic characteristics were parent‐reported; anthropometric data were collected in person. Multivariate logistic regression models were stratified by race to test the association between cumulative exposure to food insecurity and ever being diagnosed with asthma, controlling for covariates.

Results

Among NHWs, odds of asthma were highest in children in households that had two episodes of food insecurity and were ever poor (OR 2.80, 95% CI 2.69–2.92). Among NHBs, one episode of food insecurity and ever being poor were associated with the highest odds of asthma (OR 2.05, 95% CI 1.97–2.14). Among Hispanics, one episode of food insecurity alone was associated with the highest odds of asthma (OR 1.63, 95% CI 1.58–1.69). Contrasting results appeared by ethnic group for parental depression, with odds for NHWs (OR 1.74, 95% CI 1.72–1.75) higher than Hispanics (OR 1.06, 95% CI 1.05–1.08) and NHBs (OR 0.98, 95% CI 0.96–0.99). Results were adjusted for child sex, birth weight, health insurance status, overweight or obesity, and maternal nativity and education.

Conclusion

In 2014, 19% of U.S. households with children experienced food insecurity, which we have previously demonstrated is associated with asthma. These results demonstrate that asthma is associated with strong ethnic differences in life course exposure to food insecurity and poverty. Thus, recent pediatric healthcare policy urging screening for food insecurity at pediatric visits may potentially reduce interethnic health disparities in asthma outcomes.

Support or Funding Information

Ms. Mangini and Dr. Forman are supported by the David Bruton, Jr. Professorship funds.
Food Insecurity Status and Mortality in Ontario, Canada
Authors: Gundersen Craig , Tarasuk Valerie , Cheng Joyce , de Oliveira Claire , Kurdyak Paul , Dachner Naomi
Published: November 2023

Multiple negative health outcomes are linked to household food insecurity in Canada and the US. What has not been examined, though, is whether food insecurity is associated with higher risks of mortality. We examined the relationship between individuals’ food security status over a 12‐ month period and their mortality status (a) at any point since the survey and (b) within four years of the survey. We used data for 67,033 Ontario adults from the Canadian Community Health Survey linked with administrative health care data. Among individuals 18 to 64, 2.3% of food secure individuals had died at some point after the survey while over twice as many severely food insecure individuals (6.1%) had died. Among individuals over the age of 65, the figures are 24.5% and 33.1%. Even after adjusting for age, sex, education, homeownership, household composition, and neighborhood income quintile, when we look at all adults, mortality rates at any time after the survey are 95.3% higher for severely food insecure, 40.4% higher for moderately food insecure, and 26.8% higher for marginally food insecure adults versus food secure adults; when mortality within four years is considered, that rate is 83.6% higher for severely food insecure and 49.4% higher for moderately food insecure adults. Our results suggest that household food security status is a robust predictor of mortality, further indicating the importance of pursuing policies to reduce food insecurity.

Support or Funding Information

Funded by the Canadian Institutes of Health Research (FRN 115208).
Nutrition Sensitivity in Ethiopia's Productive Safety Net Programme: Tracing the Movement of an Idea in Ethiopia's Development Landscape
Authors: Warren Andrea M. , Frongillo Edward A. , Gillespie Stuart
Published: November 2023

Background

Nutrition sensitivity has emerged over the past 5–10 years as an influential idea in international development programming. The Ethiopian government has subscribed to the health and economic potential of a focus on nutrition and nutrition sensitivity more recently, as evidenced by the 2013 introduction of their comprehensive, multi‐sectoral National Nutrition Programme. In one of the first moves of its kind at this scale, the government explicitly “sensitized” the 2015 fourth iteration of their well‐known social protection scheme, the Productive Safety Net Programme (PSNP).

Objective

The objective of this qualitative study was to investigate how understandings of and negotiations toward the operationalization of the idea of nutrition sensitivity developed during the early phases of “sensitizing” a large social protection scheme to nutrition.

Methods

Sixty in‐depth, qualitative interviews were conducted with stakeholders at the international, federal, district, subdistrict, village, and household levels over a period of 18 months. Interviews were recorded or detailed notes were taken. They were coded to identify, compare, and contrast themes within and across levels. Relevant program documents were also collected and analyzed.

Results

In the Ethiopian context, the inherent flexibility within the idea of nutrition sensitivity, which allows for its key characteristic of adaptability, prevented intended audiences from being confident in their understanding of how to implement this concept. Stakeholders at all levels anticipated that pre‐existing systemic constraints around implementation capacity of both national health and agriculture programs would significantly inhibit successful implementation of nutrition‐sensitive programming within the PSNP. Despite potential implementation barriers, stakeholders indicated that the powerful, government‐backed momentum around the idea would continue, ideally leading to positive impacts on nutritional outcomes within the next decade.

Conclusions

This study provides evidence of 1) how understandings around the operationalization of nutrition sensitivity take shape and begin to materialize at multiple levels of operation and within multiple sectors, and 2) the contextual factors that influence the design and uptake of nutrition‐sensitive programming. Recommendations derived from this study are relevant for stakeholders engaged in the design, dissemination, and implementation of multi‐level and multi‐sectoral approaches to nutrition.

Support or Funding Information

This work is supported through Transform Nutrition funded by UK aid from the UK government, through the CGIAR Agriculture for Nutrition and Health Programme and through the Stories of Change Project from the Children's Investment Fund Foundation.
The Effect of Genetic Variation on the Human Milk Proteome
Authors: Lemay Danielle G , Beck Kristen L , Kwok Eric , Phinney Brett S , Korf Ian
Published: November 2023

Milk proteins provide more than amino acids to offspring. Many milk proteins have been shown to have other biological roles such as digestion, nutrient absorption, and immunodevelopment. We previously catalogued proteins in human milk by LC‐MS/MS using a reference database for the peptide spectrum matching (PSM). However, proteins can only be identified via PSM if the sequence of the protein is present in the database. To address this problem, we used RNA‐sequencing to develop a comprehensive database of protein sequences for milk samples from three subjects with different ethnicities: Caucasian, African American, and Hispanic. We then used these databases to search the spectra generated from LC‐MS/MS analysis of whole milk samples from the same three subjects. Using these custom proteome databases, we identified 85 milk proteins with genetic variation relative to the reference sequence. These 85 milk proteins contained 184 single amino acid polymorphisms and one insertion. Importantly, these genetic variants include common isoforms of the major proteins in milk such as the caseins and lactoferrin. Based on exclusive spectrum counts, some of the variants identified are more common in milk than the protein sequence derived from the reference database. Examination of the exclusive spectrum counts also demonstrates genetic differences between the milk from these subjects of different ethnicities. The presence of different isoforms of the major milk proteins may have biological consequences for offspring. Our study also suggests that genetic differences should be considered when comparing milk proteomes between different human populations.

Support or Funding Information

Funded in part by California National Primate Research Center Postdoc Pilot Grant to D.L., supplement to NIH/NCRR P51 RR00169, K.B. was supported in part by a fellowship under the Training Program in Biomolecular Technology (NIGMS‐NIH T32‐GM008799) at the University of California, Davis.
Cardiac Kids Club Improves Nutrition Knowledge, Dietary Intake, and Fitness Among 4th & 5th Graders
Authors: Beck Megan , Spence Marsha , Clay Kristen , Perry‐Burst Carolyn , Colby Sarah , Kavanagh Katie
Published: November 2023

Purpose

The purpose of Cardiac Kids Club, an afterschool obesity prevention program for 4th and 5th graders, is to create healthful nutrition behavior changes and increase fitness levels among participants.

Methods

Children from 7 schools in East Tennessee, which were selected due to high rates of overweight and obesity among students, participated in the program (n=114). The program ran for 10‐weeks, with 20 sessions that included 45 minutes of nutrition education and 1 hour of physical activity. The nutrition curriculum included didactic and interactive components, along with taste tests; the physical activity component included non‐competitive games to keep children engaged in moderate to vigorous physical activity throughout the physical activity time. Trained research assistants measured height and weight and assisted in collecting FITNESSGRAM measures pre‐ and post‐intervention. Children self‐reported dietary intake using a validated survey, the CATCH ‘EM 2: What Did You Eat Yesterday Questionnaire, and answered questions about nutrition‐related behaviors when selecting foods at home and school.

Results

From pre‐ to post‐implementation, children significantly decreased the average number of less‐healthy foods from 7.69 to 6.44 (p=0.01). Using Go, Slow and Whoa food categories to select foods increased in frequency and was significantly different pre‐ to post‐intervention (p=0.01). All FITNESS gram measurements significantly increased, including curlups, trunk lifts, sit and stretch right, sit and stretch left, push‐ups, and the mile‐run (p<0.01 for all measures). BMI percentile significantly decreased among all participants from 78.2 to 77.2 (p<0.01); further analysis revealed that pre‐ and post‐differences for participants classified as normal weight (BMI <85th percentile) did not significantly decrease, while participants classified as overweight or obese (BMI ≥85th percentile) did significantly decrease from 94.77 to 93.80 (p=0.02).

Conclusion

This research‐based obesity prevention program has the potential to positively impact the nutritional health and fitness levels of enrolled participants.

Support or Funding Information

Sponsorship from Tennova, grant funding from the East Tennessee Cardiovascular Research Foundation, 21st Century Grant Funding
Eating episodes and low calorie sweetener intake in the US adult population: NHANES 2007–2012
Authors: Marriott Bernadette Pergrin , Hunt Kelly J. , Malek Angela M. , Greenberg Danielle , St. Peter John
Published: November 2023

Based on research in rodents, use of Low Calorie Sweeteners (LCS) have been hypothesized to disrupt the expected relationship between sweet oral taste cues and post‐ingestive caloric outcomes potentially affecting dietary eating patterns, however human data is absent. To explore this proposed association we used the first 24 hour recall dietary data from the NHANES 2007–2012 (19+y;sample n=15,610) to assess by LCS intake the reported number, timing, type, and macronutrient content of eating episodes (n=83,216). Eating episodes were based on respondent‐defined intake of reported items consumed within a 15 minute window. Those who reported intake of LCS containing foods, beverages and condiments evidenced more eating episodes per day, which started earlier in the morning and lasted longer across the day, than non‐LCS episodes. In a given day, estimated macronutrient intake per eating episode and overall was significantly lower among individuals who reported LCS intakes. These data are consistent with other published reports that show a larger number of eating episodes and lower caloric intake associated with LCS consumption.

Support or Funding Information

Research Support: PepsiCo, Inc. Global R&D.

Comparing all reported intakes during eating episodes in US adults for foods & beverages with and without low calorie sweetener (LCS). (% or mean ± SEM)

No LCS (64.2%)
Yes LCS (35.8%)

Number of Episodes (n)
5.37 ±0.04
5.84 ±0.04**

Time of First Episode
7:39am ±3.0
7:16am ±4.2**

Time of Last Episode
8:22pm ±1.6
8:24pm ±2.6

Time Span of Daily Eating (all categories)**

Less than 10.9 hours/24 (%)
22.58 ±0.69
17.28 ±0.81

>10.9 to <14.2 hours/24 (%)
53.68 ±0.72
54.04 ±0.85

Greater than 14.2 hours/24 (%)
23.74 ±0.74
28.68 ±0.79

Type of Eating Episode (all categories)*

Food Only (%)
28.12 ±0.53
26.46 ±0.68

Food and Beverage (%)
43.26 ±0.59
45.42 ±0.62

Beverage Only (%)
28.62 ±0.38
28.13 ±0.48

Nutrients per Eating Episode

Grams (g)
657 ±7
608 ±7**

Energy (kcal)
415 ±3
344 ±3**

Energy Food (kcal)
307 ±2
274 ±2**

Energy Beverage (kcal)
83 ±2
46 ±1**

Energy Condment (kcal)
25 ±1
24 ±1

Energy density (kcal/g)
1.18 ±0.01
1.09 ±0.01**

Protein (g)
15.56 ±0.13
14.01 ±0.17**

Carbohydrate (g)
51.15 ±0.44
39.98 ±0.31**

Total Sugars (g)
23.86 ±0.34
16.29 ±0.16**

Dietary Fiber (g)
3.14 ±0.04
2.99 ±0.05*

Total Fat (g)
15.29 ±0.15
13.60 ±0.16**

Energy (kcal) for all eating episodes
2233 ±18
2013 ±17**

Note: P‐values compared differences between eating episodes with and without LCS by pairwise analysis of mean values and global analysis of categorical variables.

Statistically significant at p<0.05

Statistically significant at p<0.001