bluuebunny/crossref_metadata_2025_split huggingface dataset:
1381-P: GDF15 Deficiency in Brown Adipose Tissue Does Not Affect Thermogenesis, but Exacerbates Diet-Induced Obesity
Authors: JENA JAYASHREE , KATO KEVIN , MARTI ALEX A. , PEREIRA RENATA 
Published: May 2022

Growth and differentiation factor 15 (GDF15) is induced in brown adipocytes in response to thermogenic stimuli, as well as high-fat feeding in mice. However, whether brown adipose tissue (BAT) -derived GDF15 is required to regulate BAT thermogenesis or energy homeostasis is unclear. In the present study, we sought to test the hypothesis that BAT-derived GDF15 is necessary to mediate thermogenesis and systemic adaptations to diet-induced obesity (DIO) . We generated mice lacking GDF15 specifically in BAT by crossing Gdf15 floxed mice with mice harboring the Cre recombinase under the control of the Ucp1 promoter (GDF15 BAT KO) . GDF15 BAT KO mice were treated with the beta adrenoreceptor agonist CL316,243 (CL) for 5 days to induce thermogenesis, or fed a high-fat diet (60% fat content) for 12 weeks to induce DIO. CL treatment promoted a significant induction in Gdf15 mRNA levels in the BAT of WT mice, which, as expected, was prevented in KO mice. Nonetheless, serum GDF15 levels were similarly induced by CL in both WT and KO mice. CL-induced activation of thermogenic genes in BAT, such as Ucp1 and Dio2, was comparable between genotypes, and core body temperature was unchanged between WT and KO mice. After 12 weeks of high-fat feeding, KO mice had significantly increased body weight and fat mass relative to WT mice. However, food intake, locomotor activity and energy expenditure were unchanged between groups. Respiratory exchange ratio was significantly higher in KO mice, indicating a relative preference for carbohydrate as fuel. Although glucose tolerance was unchanged between genotypes, insulin sensitivity was impaired in KO mice. Taken together, our data indicates that BAT-derived GDF15 does not contribute to GDF15 circulating levels in response to CL treatment and is largely dispensable for CL-induced BAT thermogenesis. However, BAT-derived GDF15 seems to be required to regulate diet-induced weight gain and insulin sensitivity.

Disclosure
J.Jena: None. K.Kato: None. A.A.Marti: None. R.Pereira: None.

Funding
NIHDK125405
1391-P: Reduced DMPC and PMPC in Lung Surfactant Promotes SARS-CoV-2 Infection in Obesity
Authors: DU KANG , SUN LING , LUO ZICHEN , CAO YANG , SHAN JINJUN , YANG QIN 
Published: May 2022

Background: Obesity is an established risk factor for higher SARS-CoV-2 viral loads, severe COVID-pneumonia requiring hospitalization, and worse outcomes. However, the underlying mechanisms for the increased risk are not well understood. SARS-CoV-2 is a respiratory virus with the primary route of entry through lungs, where the Spike protein of SARS-CoV-2 binds to ACE2 receptor on pneumocytes. Lung surfactant produced by type II pneumocytes plays a major role in respiratory defense against infections. Surfactant predominantly contains lipids especially phosphatidylcholines (PC) and obesity is characterized by aberrant lipid metabolism. We hypothesized that altered lipid composition in lung surfactant in obesity may promote SARS-CoV-2 infection, leading to severe COVID-disease.
Methods: Lipidomic analysis of lung tissue and bronchoalveolar lavage fluid (BALF) was performed using LC-MS/MS. The effects of PCs on SARS-CoV-2 pseudovirus infection were studied in HEK293T cells with ACE2 overexpression and in Vero-E6 cells with endogenous ACE2 expression.
Results: Lipidomic analysis revealed that myristic acid containing dimyristoyl-PC (DMPC) and palmitoylmirystoyl-PC (PMPC) were commonly reduced in lung tissue and BALF from high fat diet-induced obese mice. DMPC and PMPC markedly inhibited wild type and D614G mutant SARS-CoV-2 infection in HEK293T-ACE2 and Vero-E6 cells. Feeding obese mice with trimyristin, the triglycerides of myristic acid, increased DMPC and PMPC in lung surfactant. Lipid extract from BALF of trimyristin-treated obese mice reduced wild type and D614G mutant SARS-CoV-2 infection. The inhibitory effects of DMPC and PMPC on SARS-CoV-2 infection were reversed by cholesterol.
Conclusions: The reduced DMPC and PMPC in lung surfactant contributes to the increased SARS-CoV-2 infection. Increasing DMPC and PMPC in lung surfactant may be an innovative strategy for preventing and treating severe COVID-disease in obesity.

Disclosure
K.Du: None. L.Sun: None. Z.Luo: None. Y.Cao: None. J.Shan: None. Q.Yang: None.

Funding
National Institutes of Health (R01DK121146) ;Pacific Life Foundation Fellowship to UC Irvine Diabetes Center;Chinese National Natural Science Foundation (No.81774156)
1392-P: Gut Microbiota Contributes to the Beneficial Metabolic Effects of Gelesis Hydrogel Technology
Authors: SILVESTRI ALESSANDRA , GIL-GOMEZ ANTONIO , CHIQUETTE ELAINE , DEMITRI CHRISTIAN , JONES BRYAN W. , SANNINO ALESSANDRO , RESCIGNO MARIA 
Published: May 2022

Gelesis' Oral superabsorbent hydrogels (OSH) are crosslinked cellulose-based materials that expand upon hydration in the gastrointestinal tract and are engineered to mimic the mechanical properties of masticated vegetables. One OSH prototype, denoted Gel-B, was tested in both preventative and treatment settings in murine models of diet-induced obesity. Gel-B administration blunted weight gain, reversed gut atrophy, improved metabolic parameters (glucose and insulin tolerance tests; GTT and ITT) and restored barrier function. Here, we investigated the functional role of the gut microbiome to partially explain these protective metabolic effects.
Metabolic disease was induced in both Donor (n=24) and Recipient (n=24) C57BL6/J mice via consumption of a high fat and high cholesterol/carbohydrate (HFHCC) diet for weeks (wks) . Donor mice continued on HFHCC or were treated with HFHCC+Gel-B (2 or 4%) for an additional 6 wks. After 2 wks treatment, Donor fecal samples were processed every other day for intestinal microbiota transplantation (IMT) . Recipient mice continued HFHCC and received IMT derived from either HFHCC or Gel-B (2 or 4%) treated Donors via gavage every other day for 4 wks.
At 4 wks, the HFHCC-corrected % body weight difference in Recipients was -10.8% and -9.6% for the 2% Gel-B-derived IMT (p=0.02) , and 4% Gel-B-derived IMT (p= 0.02) respectively. Glucose excursions, AUC 0-2h from GTT, were significantly reduced in both Recipient groups (p=0.for both 2% and 4% Gel-B-derived IMT) . The AUC 0-2h from ITT were significantly increased in the 4% Gel-B-derived IMT Recipients (p=0.04) and trended for the 2% Gel-B-derived IMT group (p=0.13) .
The present study demonstrates for the first time that IMT from Gel-B treated Donors confers beneficial metabolic effects in HFHCC treated mice. Future experiments will define Gel-B associated microbiota and examine engraftment and durability of IMT.

Disclosure
A.Silvestri: None. A.Gil-gomez: None. E.Chiquette: Employee; Gelesis. C.Demitri: Stock/Shareholder; Gelesis. B.W.Jones: Employee; Gelesis. A.Sannino: None. M.Rescigno: Research Support; Gelesis.
1393-P: Cardiac and Skeletal Muscles Exhibit Discordant Flux Adaptations as a Result of Western Diet–Induced Obesity
Authors: HASENOUR CLINTON M. , RAHIM MOHSIN , BEDNARSKI TOMASZ , BANERJEE DEVEENA R. , YOUNG JAMEY 
Published: May 2022

The metabolic complications of obesity are distributed throughout the body, yet studies assessing its impact on metabolic fluxes have primarily focused on single tissues. Here we use a 13C tracer approach to simultaneously quantify metabolic flux dysregulation in the liver, skeletal muscle, and heart induced by Western diet (WD) feeding in a mouse model of obesity. Male wildtype (WT) and Mc4r-/- mice (KO) were fed chow until 8wks of age, when ∼50% of the KO cohort transitioned to WD (KO+WD) for 8wks. KO and KO+WD had increased adiposity, hepatic steatosis, HOMA-IR, and reduced glucose tolerance relative to WT by 16wks of age; however, only KO+WD had extensive liver fibrosis. Stable- and radio-labeled isotopes were infused and blood was sampled from fasted, conscious, and unrestrained mice (n ≥ 6 per group) through jugular vein and carotid artery catheters, respectively. Metabolic fluxes were estimated by fitting an integrated mathematical model of liver, skeletal muscle, and cardiac metabolism to 13C enrichment measurements of plasma and tissue metabolites taken at the end of the infusion. Endogenous glucose production was elevated in both KO cohorts, with WD further increasing hepatic gluconeogenic and citric acid cycle (CAC) fluxes. Glycolytic, anaplerotic, and CAC fluxes were lower in the skeletal muscle of KO and KO+WD compared to WT, which coincided with a decrease and increase in gene expression of glycolytic and β-oxidation enzymes, respectively. In the heart, however, WD feeding increased glycolytic and CAC fluxes as well as the gene expression of glycolytic and β-oxidation enzymes. Thus, cardiac and skeletal muscles exhibit discordant flux adaptations in obese, WD-fed mice, as WD accelerates aerobic glycolysis and terminal oxidation in the heart but not skeletal muscle. We expect the multi-organ fluxomics platform described here to broadly benefit research to understand systemic metabolism in health and disease.

Disclosure
C.M.Hasenour: Employee; Eli Lilly and Company. M.Rahim: None. T.Bednarski: None. D.R.Banerjee: None. J.Young: Consultant; Pfizer Inc., Research Support; Merck & Co., Inc., Stock/Shareholder; Metalytics, Inc.

Funding
National Institutes of Health (R01DK106348, U01CA235508, T32DK101003)
1394-P: Peri-Islet Glial-Cell Expansion Occurs in Response to High-Fat Diet-Induced Obesity and Hyperglycemia
Authors: NIU JINGJING , MOSS JENNIFER B. , ROSARIO WILFREDO , ARUMUGAM RAMAMANI , HACKNEY DARYL J. , HULL-MEICHLE REBECCA L. , TONG JENNY 
Published: May 2022

Peri-islet glial cells (PIGCs) are positioned to control neuronal-endocrine-vascular cell communication within the islet, but their role in islet cell function is not known. Hypothalamic glial cells become reactive in response to high fat diet (HFD) feeding and are implicated in the pathogenesis of obesity and type 2 diabetes. We hypothesize that metabolic stress such as diet-induced obesity and hyperglycemia promote the expansion of PIGCs, similar to what has been observed in the central nervous system. To test this hypothesis, we used the glial cell marker, glial fibrillary acidic protein (GFAP) , to identify PIGCs and compared GFAP immunoreactivity in pancreas from the following groups. First, pancreas was harvested from HFD- or chow fed control C57BL/6J male mice after 2 days, 2 weeks or 8 weeks on diet (n=6-8/group) . Second, pancreas was taken from 12-wk old db/db male mice and their control littermates with or without empagliflozin (EMPA) treatment (20mg/kg/d for 6 weeks; n=4-7/group) . Islet PIGC area was quantified as GFAP-positive area/total islet area x100%. Mann-Whitney test and one-way ANOVA were used for data analysis. We found that HFD feeding increased mouse pancreatic peri-islet GFAP expression relative to chow controls at 2 days (HFD 1.4±0.2%, chow 0.8±0.1%; p=0.02) , 2 weeks (HFD 3.5±0.4%, chow 1.2±0.1%; p&lt;0.001) and 8 weeks (HFD 5.4±0.3%, chow 1.8±0.2%; p=0.002) in association with body weight gain and impaired glucose tolerance. Similar results were observed in obese and hyperglycemic db/db mouse vs. control littermates (db/db 5.0±1.4%, control 1.2±0.4%; p=0.004) . There was a trend for EMPA treatment to reduce islet PIGC area in the db/db mice (EMPA 2.0±0.5, VEH 5.0±1.4%, p=0.08) .
In conclusion, these findings indicate that islet gliosis is observed in two obese and hyperglycemic mouse models and raise the possibility that pancreatic ‘gliosis’ may have a relevant role in islet-cell function regulation under metabolic challenge.

Disclosure
J.Niu: None. J.B.Moss: None. W.Rosario: Employee; Merck & Co., Inc. R.Arumugam: None. D.J.Hackney: None. R.L.Hull-meichle: Research Support; Casma Therapeutics. J.Tong: None.

Funding
National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (R01DK097550) ;Department of Veterans Affairs (IBX004063)
1398-P: Lactobacillus rhamnosus Attenuates Depressive-Like Behavior in High-Fat Diet Fed Mice and Regulates Tyrosine Hydroxylase
Authors: SCHELL MAREIKE , WARDELMANN KRISTINA , HAUFFE ROBERT , RATH MICHAELA , CHOPRA SIMRAN , KLEINRIDDERS ANDRE 
Published: May 2022

Prevalence of depression is higher in diabetic patients compared to healthy humans due to a shared pathogenesis including insulin resistance and inflammation. These factors are also linked to intestinal dysbiosis. Interestingly, preventive intake of probiotic lactobacilli has been shown to improve dysbiosis along with mood and metabolism. Yet, a potential therapeutic role and underlying mechanism of Lactobacillus rhamnosus GG (LGG, ATCC 53103) to improve emotional behavior in diet-induced obesity is unknown.
Male C57BL/6N mice were fed a low-fat diet (LFD, 10% kcal from fat) or high-fat diet (HFD, 45% kcal from fat) for 6 weeks and followed by daily oral gavage of vehicle or 1x108 CFU of LGG. Dark-Light Box Test was used to evaluate anxiety, Mousetail Suspension Test (MST) and Splash Test were used to assess depressive-like behavior and motivation for self-care. Cecal microbiome composition was analyzed using 16S rRNA Sequencing. Plasma and CSF were collected for metabolomic analysis, and gene expression was analyzed using qPCR.
We observed that 12 weeks of HFD feeding increased anxiety and depressive-like behavior. Strikingly, LGG decreased specifically depressive-like behavior in the MST which was confirmed by the Splash Test. Metagenomics analysis revealed that HFD but not LGG alters cecal microbiome composition, indicating a transient effect. Moreover, HFD feeding significantly altered plasma lipid metabolism whereas LGG decreased branched chain amino acids which associated with improved emotional behavior. In dopaminergic brain regions, LGG restored the HFD-induced decrease of tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis, while not altering enzymes responsible for dopamine degradation.
Our data indicate that LGG attenuates specifically depressive-like behavior in HFD-fed mice with a molecular signature of restored dopamine synthesis.

Disclosure
M.Schell: Other Relationship; Novozymes A/S, Denmark. K.Wardelmann: None. R.Hauffe: None. M.Rath: None. S.Chopra: None. A.Kleinridders: Other Relationship; Novozymes.

Funding
German Ministry of Education and Research (BMBF) and the State of Brandenburg (DZD grant 82DZD00302 and BMBF grant 031B0569) .
1399-P: Quantitation of the Energy Cost of Physical Activity in Mice
Authors: SKOP VOJTECH , GUO JUEN , LIU NAILI , HALL KEVIN D. , GAVRILOVA OKSANA , REITMAN MARC L. 
Published: May 2022

Mice are widely used for diabetes and obesity research, but the quantitative contribution of physical activity to mouse energy metabolism is poorly understood. The energy cost of activity (PAEE) is typically determined by regression of total energy expenditure (TEE) versus physical activity. Confounding factors are 1) that muscle-produced heat reduces cold induced thermogenesis by brown fat and 2) that core body temperature (Tb) increases during physical activity. Minimizing cold induced thermogenesis addresses the first problem. Prior studies used housing at 30°C, but 30°C is now known to be below thermoneutrality in the dark phase. Furthermore, the Tb increase accompanying physical activity increases energy expenditure by non-activity processes; this was not considered previously. To account for these factors, we studied mice by indirect calorimetry at an ambient temperature of 35 °C while measuring Tb by telemetry and physical activity by beam break. We developed a model, partitioning TEE into PAEE and resting energy expenditure (REE) . Significant features of the model are i) physical activity measurements are aligned to the measured TEE using the time constant of the indirect calorimetry system, ii) the REE term is adjusted for the measured Tb using a Q10 (van’t Hoff coefficient) of 3.0, and iii) the REE term is scaled for body mass. In this model, the within mouse PAEE was robustly fit by linear regression, yielding PAEE of 22.5 ± 0.8 (light) and 21.7 ± 1.0 (dark) cal/1000 beam breaks (n=17) . The correlations between measured and model-calculated TEE were r = 0.888 ± 0.013 (light) and 0.888 ± 0.0 (dark) . Under usual housing conditions (ambient temperature of 23 °C) , the average physical activity was 1390 ± 130 (light) and 4940 ± 390 (dark) beam breaks/h. Based on these data, PAEE accounts for 8.6 ± 0.9 % (light) and 21.7 ± 1.8 % (dark) of TEE. This rigorous determination of PAEE advances understanding the role of physical activity in mouse energy metabolism, improving the predictive value of the mouse as a model for human disorders.

Disclosure
V.Skop: None. J.Guo: n/a. N.Liu: None. K.D.Hall: None. O.Gavrilova: None. M.L.Reitman: None.

Funding
Intramural NIDDK
1402-P: Endogenous Erythropoietin Is Protective in Mice during High-Fat Diet to Obesity and Cardiac Function while Exogenous Erythropoietin Exacerbates Cardiac Function
Authors: LEE JEEYOUNG , ROGERS HEATHER , NOGUCHI CONSTANCE T. 
Published: May 2022

Endogenous Erythropoietin (EPO) provides protection against obesity and heart function. Mice with EPO receptor restricted to erythroid tissue (ΔEPORE mice) become obese, glucose intolerant and insulin resistant. In male mice at 4 months of age, after three weeks of high fat diet feeding, ΔEPORE mice showed an increase in fat mass from to 13 grams compared to fat mass in wild type mice that more than doubled from 4 to grams. EPO treatment (i.p. 3000 U/kg, 3 times/week for three weeks) during high fat diet feeding in wild type mice reduced the increase in fat mass to 3 grams and had a minimal effect on fat mass in ΔEPORE mice. The EPO stimulated increase in hematocrit was comparable in wild type and ΔEPORE mice. Using echocardiography to measure cardiac systolic function and cardiac output after high fat diet feeding, without EPO treatment ejection fraction (%) and fractional shortening (%) of left ventricular contractility were decreased in ΔEPORE mice compared with wild type mice, suggesting that endogenous EPO provided a cardioprotective effect mediated by EPO receptor expression in non-erythroid cells. EPO treatment in wild type mice decreased peak velocity and left ventricular outflow tract velocity but there were no significant changes in ΔEPORE mice, indicating that the decreases in these parameters with EPO administration are independent of EPO stimulated erythropoiesis and mediated by EPO receptor in non-erythroid cells. EPO treatment also decreased ejection fraction and fractional shortening in wild type mice and had no further significant effect in ΔEPORE mice. These data provide evidence that while endogenous EPO may be protective for heart function, high dose EPO administration during high fat diet feeding in wild type mice compromises cardiac function. EPO modulation of heart function requires EPO receptor expression beyond erythroid cells and is distinct from EPO stimulated erythropoiesis.

Disclosure
J.Lee: None. H.Rogers: None. C.T.Noguchi: None.
1406-P: ZP8396, a Novel Amylin Analogue, Induces Weight Loss in DIO Rats with a Formulation Space at Physiological pH
Authors: SKARBALIENE JOLANTA , LUNDQVIST JOAKIM , VILLADSEN JESPER 
Published: May 2022

ZP8396, currently in phase 1, is a long-acting, amylin analogue designed to improve solubility and stability and allow for co-formulation with other peptides at physiological pH. Here we present in-vivo efficacy and formulation design space of ZP8396. The acute effects on body weight (BW) loss after a single s.c. injection of ZP8396 (0,5, 3, 30, 300 nmol/kg) were measured in lean rats and monitored for 96 hours after dosing. The ability of ZP8396 (1, 3, and 15 nmol/kg, s.c., every 2nd day for 21 days) to reduce BW was tested in diet-induced obese (DIO) rats. ZP8396, at concentration supporting pharmacological relevant human doses, is stable in an aqueous formulation at neutral pH and shows no aggregation potential. ZP8396 is compatible with different physiological buffer systems and isotonic agents, commonly used for commercial medicinal products (Table 1) . Formulation of ZP8396 at physiological pH induces a significant BW loss in both lean and DIO rats vs. vehicle group. A significant BW loss was observed from start of the dosing and throughout the study period.
In conclusion, ZP8396 potently induces BW loss in lean and DIO rats and allows for aqueous stable formulation at neutral pH which provides opportunities for co-formulation with other peptides for optimal BW loss. Further preclinical characterization of co-formulation of ZP8396 with different peptides for weight management is ongoing.

Disclosure
J.Skarbaliene: Employee; Zealand Pharma A/S, Stock/Shareholder; Zealand Pharma A/S. J.Lundqvist: Employee; Zealand Pharma A/S. J.Villadsen: Employee; Zealand Pharma A/S.
1409-P: Revealing Heterogeneity in Human White Adipose Tissue at Single-Cell Level
Authors: EFTHYMIOU VISSARION , KODANI SEAN , GUPTA ANUSHKA , SHAMSI FARNAZ , STREETS AARON , TSENG YU-HUA , PATTI MARY-ELIZABETH 
Published: May 2022

White adipose tissue is characterized by substantial functional heterogeneity based on anatomic location and developmental lineages. Such differences may contribute to depot-dependent differences in adipose regulation of systemic metabolism and the relative impact of adipose distribution (e.g. subcutaneous, SQ, vs. intraabdominal, IA) on risk for type 2 diabetes. While mouse adipose depot heterogeneity at the single-cell level has recently been explored, comparative analysis of human white fat depots is still in its infancy.Hereby, we establish a single-nucleus RNA sequencing (snRNA Seq) method for isolating and sequencing intact single nuclei from frozen human WAT biopsies. Using this approach, we analyzed the transcriptome of individual nuclei from 22 WAT SQ or IA biopsies (SQ, 12 IA, 3 paired) acquired from subjects (16 females, 3 males) with or without type 2 diabetes (T2D) across a wide BMI range (Mean+/-SD = 45.4+/-10.3 kg/m2. Range: 23.6 - 60.9 kg/m2) . We show that both SQ and IA human fat depots demonstrate substantial cell-to-cell heterogeneity, and identify multiple adipose and non-adipose-related cell types resident in both tissues. Our analysis identifies several novel subclusters, including two distinct mature adipocyte subclusters, characterized by low vs. high adiponectin expression and thus potentially contributing to adipose-mediated effects on systemic metabolism. Moreover, we identify a novel cluster present in both SQ and IA depots, with a unique transcriptomic signature marked by DAPK1 and enrichment for hedgehog signaling and endocytosis KEGG terms. Comprehensive cross-sample integrative bioinformatics analysis using the software tools scVI and VISION reveals distinct molecular markers and transcriptomic signatures between depots, between clusters, and across a range of BMI, that may serve as promising targets for understanding the mechanism by which specific adipose-resident cell populations mediate metabolic risk associated with adiposity.

Disclosure
V.Efthymiou: None. S.Kodani: None. A.Gupta: None. F.Shamsi: None. A.Streets: None. Y.Tseng: Consultant; Cellarity. M.Patti: Consultant; AstraZeneca, Eiger BioPharmaceuticals, Hanmi Pharm. Co., Ltd., MBX Biosciences, Poxel SA, Other Relationship; Fractyl Health, Inc., Xeris Pharmaceuticals, Inc., Research Support; Dexcom, Inc.

Funding
Chan Zuckerberg Initiative (CZI)