Biochemical Phenomena, Metabolism, and Nutrition Commons^™

Tfeb Induces Mitochondrial Itaconate Synthesis To Suppress Bacterial Growth In Macrophages, Ev-Marie Schuster, Maximilian W Epple, Katharina M Glaser, Michael Mihlan, Kerstin Lucht, Julia A Zimmermann, Anna Bremser, Aikaterini Polyzou, Nadine Obier, Nina Cabezas-Wallscheid, Eirini Trompouki, Andrea Ballabio, Jörg Vogel, Joerg M Buescher, Alexander J Westermann, Angelika S Rambold

Duncan NRI Faculty and Staff Publications

Successful elimination of bacteria in phagocytes occurs in the phago-lysosomal system, but also depends on mitochondrial pathways. Yet, how these two organelle systems communicate is largely unknown. Here we identify the lysosomal biogenesis factor transcription factor EB (TFEB) as regulator for phago-lysosome-mitochondria crosstalk in macrophages. By combining cellular imaging and metabolic profiling, we find that TFEB activation, in response to bacterial stimuli, promotes the transcription of aconitate decarboxylase (Acod1, Irg1) and synthesis of its product itaconate, a mitochondrial metabolite with antimicrobial activity. Activation of the TFEB-Irg1-itaconate signalling axis reduces the survival of the intravacuolar pathogen Salmonella enterica serovar Typhimurium. TFEB-driven …

Fatty Acid Translocase: A Culprit Of Lipid Metabolism Dysfunction In Disease, Joseph E Rupert, Mikhail G Kolonin

Faculty, Staff and Student Publications

Dysregulation of lipid deposition into and mobilization from white adipose tissue (WAT) underlies various diseases. Long-chain fatty acids (LCFA) and cholesterol trafficking in and out of adipocytes is a process relying on transporters shuttling lipids from the plasma membrane (PM) to lipid droplets (LD). CD36 is the fatty acid translocase (FAT) that transports LCFA and cholesterol across the PM. Interactions of CD36 with proteins PHB1, ANX2, and CAV1 mediate intercellular lipid transport between adipocytes, hematopoietic, epithelial, and endothelial cells. Intracellularly, the FAT complex has been found to regulate LCFA trafficking between the PM and LD. This process is regulated by …

Activating Connexin43 Gap Junctions Primes Adipose Tissue For Therapeutic Intervention, Yi Zhu, Na Li, Mingyang Huang, Xi Chen, Yu A An, Jianping Li, Shangang Zhao, Jan-Bernd Funcke, Jianhong Cao, Zhenyan He, Qingzhang Zhu, Zhuzhen Zhang, Zhao V Wang, Lin Xu, Kevin W Williams, Chien Li, Kevin Grove, Philipp E Scherer

Faculty, Staff and Students Publications

Adipose tissue is a promising target for treating obesity and metabolic diseases. However, pharmacological agents usually fail to effectively engage adipocytes due to their extraordinarily large size and insufficient vascularization, especially in obese subjects. We have previously shown that during cold exposure, connexin43 (Cx43) gap junctions are induced and activated to connect neighboring adipocytes to share limited sympathetic neuronal input amongst multiple cells. We reason the same mechanism may be leveraged to improve the efficacy of various pharmacological agents that target adipose tissue. Using an adipose tissue-specific Cx43 overexpression mouse model, we demonstrate effectiveness in connecting adipocytes to augment metabolic …

Crispr/Cas13 Effectors Have Differing Extents Of Off-Target Effects That Limit Their Utility In Eukaryotic Cells, Yuxi Ai, Dongming Liang, Jeremy E Wilusz

Faculty, Staff and Students Publications

CRISPR/Cas13 effectors have garnered increasing attention as easily customizable tools for detecting and depleting RNAs of interest. Near perfect complementarity between a target RNA and the Cas13-associated guide RNA is required for activation of Cas13 ribonuclease activity. Nonetheless, the specificity of Cas13 effectors in eukaryotic cells has been debated as the Cas13 nuclease domains can be exposed on the enzyme surface, providing the potential for promiscuous cleavage of nearby RNAs (so-called collateral damage). Here, using co-transfection assays in Drosophila and human cells, we found that the off-target effects of RxCas13d, a commonly used Cas13 effector, can be as strong as …

Phosphatidylserine And Phosphatidylethanolamine Asymmetry Have A Negligible Effect On The Global Structure, Dynamics, And Interactions Of The Kras Lipid Anchor, Mussie K Araya, Alemayehu A Gorfe

Faculty, Staff and Student Publications

The intrinsically disordered C-terminus of the prominent oncogenic protein KRAS-4B (KRAS) selectively interacts and clusters with phosphatidylserine (PS) lipids in the plasma membrane (PM). This 11-residue segment, called tK, contains a polybasic domain (PBD) of six contiguous lysine residues and a farnesylated cysteine. Previous molecular dynamics (MD) simulation studies of tK in phosphatidylcholine (PC)/PS bilayers have suggested that backbone conformational dynamics modulate tK-PS interactions. These simulations have been conducted in symmetric membranes whereas the PM is compositionally asymmetric, with the inner leaflet, where KRAS is localized, being enriched with PS and phosphatidylethanolamine (PE) lipids. To examine if bilayer asymmetry affects …

Evaluation Of Long-Chain Fatty Acid Respiration In Neonatal Mouse Cardiomyocytes Using Seahorse Instrument, Aude Angelini, Xinchun Pi, Liang Xie

Faculty, Staff and Students Publications

Metabolic switches play a critical role in the pathophysiology of cardiac diseases, including heart failure. Here, we describe an assay for long-chain fatty acid oxidation in neonatal mouse cardiomyocytes by using a SeaHorse Flux Analyzer (Agilent). This protocol is a simplified but robust adaptation of the standard protocol that enables metabolic measurements in cells isolated from transgenic mouse models, which can be timesaving and informative. Cell isolation and culture represent a critical point that may require bench optimization.

For complete details on the use and execution of this protocol, please refer to Angelini et al. (2021).

Estimating Circadian Phase In Elementary School Children: Leveraging Advances In Physiologically Informed Models Of Circadian Entrainment And Wearable Devices, Jennette P Moreno, Kevin M Hannay, Olivia Walch, Hafza Dadabhoy, Jessica Christian, Maurice Puyau, Abeer El-Mubasher, Fida Bacha, Sarah R Grant, Rebekah Julie Park, Philip Cheng

Faculty, Staff and Students Publications

STUDY OBJECTIVES: Examine the ability of a physiologically based mathematical model of human circadian rhythms to predict circadian phase, as measured by salivary dim light melatonin onset (DLMO), in children compared to other proxy measurements of circadian phase (bedtime, sleep midpoint, and wake time).

METHODS: As part of an ongoing clinical trial, a sample of 29 elementary school children (mean age: 7.4 ± .97 years) completed 7 days of wrist actigraphy before a lab visit to assess DLMO. Hourly salivary melatonin samples were collected under dim light conditions (<5 >lx). Data from actigraphy were used to generate predictions of circadian …

Context Matters: Preliminary Evidence That The Association Between Positive Affect And Adiposity In Infancy Varies In Social Vs Non-Social Situations, Alexis C Wood, Shabnam R Momin, Mackenzie K Senn, David J Bridgett

Children’s Nutrition Research Center Staff Publications

Previous studies have suggested that infants high in negative affect have higher levels of adiposity, arising in part via changes in nutrition (e.g., “feeding to soothe”). Few studies have examined whether positive affect shows similar or inverse associations with adiposity. The current study examined cross-sectional and longitudinal relationships between adiposity and observations of positive affect in both a social and a non-social context, using data from infants at four (n = 125) and 12 (n = 80) months of age. Our analyses did not find any cross-sectional associations between positive affect and adiposity (all p > 0.05). However, in the longitudinal …

Tomatoes, Lycopene, And Prostate Cancer: What Have We Learned From Experimental Models?, Nancy E Moran, Jennifer M Thomas-Ahner, Lei Wan, Krystle E Zuniga, John W Erdman, Steven K Clinton

Children’s Nutrition Research Center Staff Publications

Human epidemiology suggests a protective effect of tomatoes or tomato phytochemicals, such as lycopene, on prostate cancer risk. However, human epidemiology alone cannot reveal causal relations. Laboratory animal models of prostate cancer provide opportunities to investigate hypotheses regarding dietary components in precisely controlled, experimental systems, contributing to our understanding of diet and cancer risk relations. We review the published studies evaluating the impact of tomatoes and/or lycopene in preclinical models of prostate carcinogenesis and tumorigenesis. The feeding of tomatoes or tomato components demonstrates anti-prostate cancer activity in both transplantable xenograft models of tumorigenesis and models of chemically- and genetically-driven carcinogenesis. …

French-Fried Potato Consumption And Energy Balance: A Randomized Controlled Trial, Daniel L Smith, Rebecca L Hanson, Stephanie L Dickinson, Xiwei Chen, Amy M Goss, John B Cleek, W Timothy Garvey, David B Allison

Children’s Nutrition Research Center Staff Publications

Background: Epidemiologic observations suggest increased potato consumption correlates with weight gain, adiposity, and diabetes risk, whereas nut consumption is associated with weight control and metabolic health. Randomized controlled trial (RCT) data indicate humans respond to changes in energy intake in single dietary components and compensate for extra energy consumed.

Objectives: We completed an RCT testing whether increased daily potato consumption influences energy balance [specifically, fat mass (FM)] compared with calorie-matched almond consumption.

Methods: A 30-d RCT of 180 adults prescribed calorie-matched (300 kcal/d, n = 60 participants/group) than consumed 1 of the following: 1) almonds (almond group), 2) French fries …

Associations Between Adherence To The Dietary Approaches To Stop Hypertension (Dash) Diet And Six Glucose Homeostasis Traits In The Microbiome And Insulin Longitudinal Evaluation Study (Miles), Gautam Ramesh, Alexis C Wood, Matthew A Allison, Stephen S Rich, Elizabeth T Jensen, Yii-Der I Chen, Jerome I Rotter, Alain G Bertoni, Mark O Goodarzi

Children’s Nutrition Research Center Staff Publications

Background and aims: The DASH diet conveys protection against type 2 diabetes mellitus (T2D) Via plant-based and non-plant-based recommendations. Research has not identified which glucose homeostasis pathways are improved. We examined associations between adherence to a DASH diet and six glucose homeostasis traits, probing whether associations could be attributed to the plant-based (DASH-P) and/or non-plant based (DASH-NP) components.

Methods and results: We included data from 295 adults without T2D (age 59.3 ± 9.00 years; 63.46% non-Hispanic White and 36.54% African American, self-reported race ancestry) participating in the Microbiome and Insulin Longitudinal Evaluation Study (MILES). An oral glucose tolerance test (OGTT) …

Circadian Disruption Of Hippocampus In An Early Senescence Male Mouse Model, Jennifer A Davis, Jodi R Paul, Mugdha V Mokashi, Stefani A Yates, Daniel J Mount, Hira A Munir, Lacy K Goode, Martin E Young, David B Allison, Karen L Gamble

Children’s Nutrition Research Center Staff Publications

Age-related cognitive decline and disruptions in circadian rhythms are growing problems as the average human life span increases. Multiple strains of the senescence-accelerated mouse (SAM) show reduced life span, and the SAMP8 strain in particular has been well documented to show cognitive deficits in behavior as well as a bimodal pattern of circadian locomotor activity. However, little is known about circadian regulation within the hippocampus of these strains of mice. Here we test the hypothesis that in this early senescence model, disruption of the molecular circadian clock in SAMP8 animals drives disrupted behavior and physiology. We found normal rhythms in …

The Effect Of Reduced Cp, Synthetic Amino Acid Supplemented Diets On Growth Performance And Nutrient Excretion In Wean To Finish Swine, Caitlin E Vonderohe, Kayla M Mills, Shule Liu, Matthew D Asmus, Emily R Otto-Tice, Brian T Richert, Ji-Qin Ni, John Scott Radcliffe

Children’s Nutrition Research Center Staff Publications

Mixed sex pigs (n = 720) were placed in 12 rooms (Purdue Swine Environmental Research Building) to measure the effect of reduced crude protein (CP), amino acid (AA)-supplemented diets on growth and the carcass. Pigs were blocked by body weight (BW) and gender and allotted to room and pen (10 mixed-sex pigs/pen). Pigs were fed a nine-phase, wean-finish program. Control pigs consumed corn-soybean meal-distiller’s dried grains with solubles (DDGS) diets containing no to minimal (Met) synthetic AA. The 2X diet was formulated to meet the seventh most-limiting AA, and balanced using synthetic AAs to meet all AA needs. The …

The Hypothalamus For Whole-Body Physiology: From Metabolism To Aging, Tiemin Liu, Yong Xu, Chun-Xia Yi, Qingchun Tong, Dongsheng Cai

Children’s Nutrition Research Center Staff Publications

Obesity and aging are two important epidemic factors for metabolic syndrome and many other health issues, which contribute to devastating diseases such as cardiovascular diseases, stroke and cancers. The brain plays a central role in controlling metabolic physiology in that it integrates information from other metabolic organs, sends regulatory projections and orchestrates the whole-body function. Emerging studies suggest that brain dysfunction in sensing various internal cues or processing external cues may have profound effects on metabolic and other physiological functions. This review highlights brain dysfunction linked to genetic mutations, sex, brain inflammation, microbiota, stress as causes for whole-body pathophysiology, arguing …

Association Of Alcohol Use And Physical Activity With Body Mass Index In Mexican-Origin Adults, Natalia I Heredia, Qiong Dong, Shine Chang, Lorna H Mcneill

Faculty, Staff and Student Publications

BACKGROUND: Studies across racial/ethnic groups indicate that physical activity (PA) and alcohol consumption are positively associated, and that alcohol consumption is negatively associated with body mass index (BMI), but this relationship is less often evaluated in Hispanics. The purpose of this study was to assess the relationships between alcohol consumption, PA, and BMI in Hispanic adults.

METHODS: In this secondary data analysis of a Mexican-American cohort, we collected self-reported PA, alcohol consumption, and demographics, and measured height and weight. Linear regression assessed the association between PA and alcohol consumption with BMI, controlling for covariates. Total sample for analyses was n …

Co-Transmitting Neurons In The Lateral Septal Nucleus Exhibit Features Of Neurotransmitter Switching, Patrick J Hunt, Mikhail Kochukov, Brandon T Pekarek, Benjamin D W Belfort, Juan M Romero, Jessica L Swanson, Benjamin R Arenkiel

Faculty, Staff and Students Publications

The lateral septal nucleus (LSN) is a highly interconnected region of the central brain whose activity regulates widespread circuitry. As such, the mechanisms that govern neuronal activity within the LSN have far-reaching implications on numerous brain-wide nuclei, circuits, and behaviors. We found that GABAergic neurons within the LSN express markers that mediate the release of acetylcholine (ACh). Moreover, we show that these vGATLSN neurons release both GABA and ACh onto local glutamatergic LSN neurons. Using both short-term and long-term neuronal labeling techniques we observed expression of the cholinergic neuron marker Choline Acetyltransferase (ChAT) in vGATLSN neurons. These findings provide evidence …

Parent-Perceived Neighbourhood Environment, Parenting Practices And Preschool-Aged Children Physical Activity And Screen Time: A Cross-Sectional Study Of Two Culturally And Geographically Diverse Cities, Ester Cerin, Anthony Barnett, Tom Baranowski, Rebecca E Lee, Robin R Mellecker, Yi Nam Suen, Jason A Mendoza, Deborah I Thompson, Teresia M O'Connor

Children’s Nutrition Research Center Staff Publications

BACKGROUND: Preschool-aged children's physical activity (PA) and screen time (ST) are important health-related behaviours likely influenced by PA opportunities, parental perceptions of neighbourhood safety and parenting practices pertaining to PA and ST. How these factors interact to impact on young children's PA and ST, and whether their effects are generalisable across cultures and geographical location is not known. This study addressed these knowledge gaps by conducting pooled analyses of comparable data from two culturally and geographically diverse samples - Chinese parent-child dyads from an ultra-dense city (Hong Kong, China) and Latino parent-child dyads from a low-density city (Houston, USA).

METHODS: …

The Ventromedial Hypothalamic Nucleus: Watchdog Of Whole-Body Glucose Homeostasis, Longlong Tu, Makoto Fukuda, Qingchun Tong, Yong Xu

Children’s Nutrition Research Center Staff Publications

The brain, particularly the ventromedial hypothalamic nucleus (VMH), has been long known for its involvement in glucose sensing and whole-body glucose homeostasis. However, it is still not fully understood how the brain detects and responds to the changes in the circulating glucose levels, as well as brain-body coordinated control of glucose homeostasis. In this review, we address the growing evidence implicating the brain in glucose homeostasis, especially in the contexts of hypoglycemia and diabetes. In addition to neurons, we emphasize the potential roles played by non-neuronal cells, as well as extracellular matrix in the hypothalamus in whole-body glucose homeostasis. Further, …

Evaluation Of A Circadian Rhythm And Sleep-Focused Mobile Health Intervention For The Prevention Of Accelerated Summer Weight Gain Among Elementary School-Age Children: Protocol For A Randomized Controlled Feasibility Study, Jennette P Moreno, Hafza Dadabhoy, Salma Musaad, Tom Baranowski, Debbe Thompson, Candice A Alfano, Stephanie J Crowley

Children’s Nutrition Research Center Staff Publications

Background: The i♥rhythm project is a mobile health adaptation of interpersonal and social rhythm therapy designed to promote healthy sleep and behavioral rhythms among 5-8-year olds during summer for the prevention of accelerated summer weight gain.

Objective: This pilot study will examine the feasibility, acceptability, and preliminary efficacy of the i♥rhythm intervention. This will ensure that the research protocol and procedures work as desired and are acceptable to families in preparation for the fully powered randomized controlled trial. The proposed study will examine the willingness of participants to participate in the intervention and determine whether modifications to the intervention, procedures, …

Fibroblast Growth Factor 15/19 Expression, Regulation, And Function: An Overview, Greg Guthrie, Caitlin Vonderohe, Douglas Burrin

Children’s Nutrition Research Center Staff Publications

Since the discovery of fibroblast growth factor (FGF)-19 over 20 years ago, our understanding of the peptide and its role in human biology has moved forward significantly. A member of a superfamily of paracrine growth factors regulating embryonic development, FGF19 is unique in that it is a dietary-responsive endocrine hormone linked with bile acid homeostasis, glucose and lipid metabolism, energy expenditure, and protein synthesis during the fed to fasted state. FGF19 achieves this through targeting multiple tissues and signaling pathways within those tissues. The diverse functional capabilities of FGF19 is due to the unique structural characteristics of the protein and …