Lipid Metabolism Research Articles

Coffee Bioactive N-Methylpyridinium: Unveiling Its Antilipogenic Effects by Targeting De Novo Lipogenesis in Human Hepatocytes.

Type 2 diabetes and nonalcoholic fatty liver diseases (NAFLDs) are promoted by insulin resistance (IR), which alters lipid homeostasis in the liver. This study aims to investigate the effect of N-methylpyridinium (NMP), a bioactive alkaloid of coffee brew, on lipid metabolism in hepatocytes. The effect of NMP in modulating lipid metabolism is evaluated at physiological concentrations in a diabetes cell model represented by HepG2 cells cultured in a high-glucose medium. Hyperglycemia triggers lipid droplet accumulation in cells and enhances the lipogenic gene expression, which is transactivated by sterol regulatory element binding protein-1 (SREBP-1). Lipid droplet accumulation alters the redox status and endoplasmic reticulum (ER) stress, leading to the activation of the unfolded protein response and antioxidative pathways by X-Box Binding Protein 1(XBP-1)/eukaryotic Initiation Factor 2 alpha (eIF2α) Protein Kinase RNA-Like ER Kinase and nuclear factor erythroid 2-related factor 2 (NRF2), respectively. NMP induces the phosphorylation of AMP-dependent protein kinase (AMPK) and acetyl-CoA carboxylase α (ACACA), and improves the redox status and ER homeostasis, essential steps to reduce lipogenesis and lipid droplet accumulation. These results suggest that NMP may be beneficial for the management of T2D and NAFLD by ameliorating the cell oxidative and ER homeostasis and lipid metabolism.

Analysis of Differential Gene Expression under Acute Lead or Mercury Exposure in Larval Zebrafish Using RNA-Seq

This study was first conducted to investigate the effects of acute lead exposure on developing zebrafish embryos or larvae from 24 to 120 h post-fertilization (hpf). Our data showed that treatment with 50–200 μM lead significantly affected larval survivability and morphology compared to the respective control. Second, we chose 120 hpf larvae treated with 12.5 μM lead for RNA sequencing due to its exposure level being sufficient to produce toxic effects with minimum death and lead bioaccumulation in developing zebrafish. A total of 137.45 million raw reads were obtained, and more than 86% of clean data were mapped to the zebrafish reference genome. Differential expression profiles generated 116 up- and 34 down-regulated genes upon lead exposure. The most enriched GO terms for representative DEGs were ion transport and lipid metabolism. Third, a comparison with the dataset of mercury-regulated gene expression identified 94 genes (64 up-regulated and 30 down-regulated) for exposure specific to lead, as well as 422 genes (338 up-regulated and 84 down-regulated) for exposure specific to mercury. In addition, 56 genes were co-regulated by micromolar mercury and lead treatment, and the expression of thirteen genes, including mt2, ctssb.1, prdx1, txn, sqrdl, tmprss13a, socs3a, trpv6, abcb6a, gsr, hbz, fads2, and zgc:92590 were validated by qRT-PCR. These genes were mainly associated with metal ion binding, proteolysis, antioxidant activity, signal transduction, calcium ion or oxygen transport, the fatty acid biosynthetic process, and protein metabolism. Taken together, these findings help better understand the genome-wide responses of developing zebrafish to lead or mercury and provide potential biomarkers for acute exposure to toxic metals.

7492 Fibroblast Growth Factor 21 In The Diagnosis And Treatment Of Metabolic Disorders

Abstract Disclosure: H.M. Heshmati: None. H.S. Abu-Lebdeh: None. Background: Fibroblast growth factor 21 (FGF21), a member of the human FGF superfamily, is a 181 amino acid peptide hormone primarily produced by the liver. The gene of FGF21, located on chromosome 19, was cloned in 2000. FGF21 is involved in the maintenance of metabolic homeostasis. This review presents an update on the relevance of FGF21 in the diagnosis and treatment of metabolic disorders including obesity, nonalcoholic fatty liver disease (NAFLD), dyslipidemia, and type 2 diabetes. Methods: A systematic search of literature was conducted using the search terms fibroblast growth factor 21, obesity, nonalcoholic fatty liver disease, dyslipidemia, and type 2 diabetes. Results: FGF21 is a stress hormone with effects on energy expenditure and metabolism of lipids and glucose. FGF21 exerts its endocrine action in the central nervous system and adipose tissue. The serum FGF21 levels in normal subjects increase with aging. Stressful conditions (e.g., fasting status, protein restriction, exercise, metabolic disorders, kidney diseases, cardiovascular diseases, and sepsis) increase FGF21 secretion. Serum FGF21 levels are increased in obesity, NAFLD, dyslipidemia, and type 2 diabetes. Some of these patients may have a state of FGF21 resistance. The resistance to FGF21 is related, at least in part, to the presence of high circulating levels of fibroblast activation protein, a protease that inactivates FGF21. It has been suggested that the exercise-induced weight loss can be due to increased FGF21 secretion and decreased FGF21 resistance in adipose tissue. Serum FGF21 level has the potential to be used as a biomarker for early diagnosis of metabolic disorders (e.g., NAFLD and type 2 diabetes). Based on different metabolic properties of FGF21, FGF21-based therapy has been considered as an attractive approach for the treatment of metabolic disorders. Since native FGF21 has poor pharmacodynamic properties (e.g., short half-life and proteolytic cleavage by proteases), long-acting FGF21 analogs (e.g., LY2405319, PF-05231023, pegozafermin, AKR-001, and LLF580) have been synthesized and tested in clinical trials for the treatment of obesity, NAFLD, dyslipidemia, and type 2 diabetes. The available results show that FGF21 analogs can reduce body weight, liver fat, blood lipids, and fasting insulin/insulin resistance. Overall, the treatment with these analogs is safe and well tolerated. Conclusion: FGF21 is a predominantly liver-derived peptide hormone regulating energy expenditure and metabolism of lipids and glucose. Serum FGF21 levels are increased in several metabolic disorders including obesity, NAFLD, dyslipidemia, and type 2 diabetes. FGF21 is an attractive target for the treatment of these metabolic disorders. Despite some promising results observed with the use of FGF21 analogs, more clinical studies are needed before recommending FGF21-based therapies in metabolic disorders. Presentation: 6/2/2024

7885 Thyroid Hormone Stimulates Heaptic Lipid Metabolism in the Resolution of Liver Fibrosis

Abstract Disclosure: A. Mendoza: None. C. Wang: None. A. Lugo: None. V. Rodrigues: None. S. Houghton: None. D. Redmond: None. A. Hollenberg: None. Metabolic dysfunction-associated steatotic liver disease (MASLD) progression to steatohepatitis and fibrosis is a global health burden, leading to liver failure and death. While the pathogenesis is complex, dysregulated lipid metabolism plays a crucial role. Thyroid hormones (THs) are key metabolic regulators in the liver, promoting lipogenesis and fatty acid oxidation. Previously, we demonstrated that the carbohydrate-responsive element binding protein (ChREBP) is a critical mediator of both these processes in hepatocytes, acting downstream of the thyroid hormone receptor beta1 (TRβ1). Interestingly, while ChREBP ablation abolished TH-induced lipogenesis through downregulation of lipogenic gene expression, its role in TH-mediated fatty acid oxidation remained unclear, suggesting a multifaceted role for ChREBP in TH-regulated hepatic metabolism. Given the critical role of lipid metabolism in the progression of MASLD to metabolic dysfunction-associated steatohepatitis (MASH) and fibrosis, we aim to delineate the mechanisms by which TH promotes the regression of fibrosis. Here, we used a carbon tetrachloride (CCL4) model of liver fibrosis in TRβ1KO and ChREBPKO mice (0.4 ul/g biweekly, 9 injections). All mice in the experiments were also on a PTU-Low Iodine diet to induce hypothyroidism. In the last week of the protocol, all mice were sorted into two groups which received either water or T3 (1ug/ml). 24 hours after the last CCL4 injection all mice were sacrificed and the livers were harvested and prepared for analysis. Herein we show that T3 promotes the resolution of liver fibrosis in wild-type mice. Importantly, this resolution was abolished in both TRβ1 and ChREBP KO mice demonstrating this pathways essential role in TH-induced resolution of fibrosis. RNA-Seq analysis of TRβ1KO mice demonstrated a dual mechanism of TH action: 1. TH upregulates gene expression in multiple metabolic pathways, suggesting a rescue of hepatic metabolism towards normal liver function and 2., TH has antifibrotic action via downregulation of pathways controlling extracellular matrix synthesis and inflammation, key drivers of fibrosis. Strikingly, ChREBP was dispensable for the antifibrotic action of TH suggesting that the ChREBP-dependent regulation of hepatic metabolism is critical for the resolution of fibrosis mediated by TH. To identify novel metabolic pathways regulated by TH via ChREBP, we intersected liver mRNA-seq from TRβ1KO mice with liver-specific ChREBP Chip-Seq and identifed multiple targets regulating autophagy that require ChREBP for their activation after TH treatment. These data suggest that the ability of ChREBP to regulate TH-induced fatty-acid oxidation is mediated by the upregulation of autophagy. This supports the notion that the ability of T3 to promote the resolution of liver fibrosis is primarily dependent of it’s ability to stimulate hepatic fatty acid metabolism. Presentation: 6/1/2024

Study on the Mechanism of Guizhi Fuling Decoction in Treating Hyperlipidemia Based on Network Pharmacology and Experimental Methods

Background Hyperlipidemia, caused by abnormal lipid metabolism, has become a significant health concern, especially in younger populations. While statins are commonly used for treatment, they often cause severe side effects with long-term use, leading to increased interest in finding natural alternatives. Purpose This study aimed to investigate how Guizhi Fuling Decoction (GZFL) treats hyperlipidemia using network pharmacology and experimental validation. Materials and Methods Network pharmacology analyzed GZFL’s active components, targets, and treatment mechanisms for hyperlipidemia. Hyperlipidemia rat and high-fat cell models were established. Experimental validation included enzyme-linked immunosorbent assay, Western blot, quantitative polymerase chain reaction, Oil Red O staining, and other methods. Statistical analysis was performed using one-way analysis of variance followed by Tukey’s post hoc test for multiple comparisons. Pearson correlation analysis was used to identify correlations between key protein expressions and lipid levels. Results GZFL comprises 85 active components and targets 218 proteins. Hyperlipidemia involves 3,852 targets, with 175 overlapping targets. Key targets included estrogen receptor 1, prostaglandin-endoperoxide synthase 2, interleukin-6 (IL-6), protein kinase B (AKT) 1, tumor necrosis factor, interleukin-1 beta, peroxisome proliferator-activated receptor gamma (PPARG), tumor protein p53 (TP53), and fructo oligosaccharide (FOS). Major active components were quercetin, phytosterols, kaempferol, and baicalein. Enrichment analysis highlighted processes like lipopolysaccharide response and lipid signaling pathways. Animal studies showed GZFL significantly reduced serum total cholesterol, triglycerides, and low-density lipoprotein cholesterol levels, and increased apolipoprotein A1 ( p < 0.05). Western blot indicated that GZFL influenced AKT, TP53, IL-6, PPARγ expression, and mRNA levels in the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway ( p < 0.01). Serum pharmacology experiments demonstrated GZFL-medicated serum reduced lipid droplet formation in high-fat cell models. Conclusion GZFL contains multiple pharmacologically active components, such as quercetin, phytosterols, and kaempferol, which can influence lipid metabolism. It may exert its effects by regulating proteins like AKT, TP53, IL-6, and PPARγ, participating in lipid and atherosclerosis signaling pathways and the PI3K/AKT/mTOR pathway.

7345 Study on the correlation between the levels of myokines and metabolic abnormality in obese children

Abstract Disclosure: L. Ouyang: None. M. Li: None. F. Yang: None. Objective: There are limited drug options to treat childhood obesity. Studies have found that myokines play an important role in the mechanism of exercise in the treatment of obesity. However, the correlation between myokines and metabolic abnormalities in obese children is still unclear. The purpose of this study is to analyze the correlation between the levels of myokines and metabolic abnormalities in obese children to provide the basis for the future application of myokines in childhood obesity. Methods: 41 obese children who visited the pediatric clinic of our hospital from March to October 2022 were enrolled, and 11 healthy non-obese children who had a regular physical examination in the pediatric clinic during the same period were enrolled. Basic information, anthropological indicators and biochemical indicators were collected. Human myokine magnetic bead panel was used to detect serum myokine levels including irisin, FGF21, BDNF, LIF, MSTN, IL 6, and IL 15. Difference analysis, rank sum test and Spearman analysis were used to conduct the correlation between the levels of myokines and metabolic abnormalities in obese children. Results: We found that the BMI-SDS and body fat rate of obese children with abnormal metabolism was higher than those with normal metabolism status(p<0.05). Children with abnormal glucose metabolism had an increased risk of abnormal lipid metabolism and hyperuricemia(p < 0.05), and children with abnormal lipid metabolism had an increased risk of hyperuricemia and hypertension(p<0.05). The obese children with abnormal glucose and lipid metabolism had an increased risk of abnormal purine metabolism. The levels of leukemia inhibitory factor and brain-derived neurotrophic factor in obese children were significantly higher than those in non-obese children (p<0.05), and the level of fibroblast growth factor 21 in obese children with abnormal metabolism was significantly higher than that in children with normal metabolism (p<0.05), respectively. There was a significant positive correlation between BMI-SDS and the levels of irisin, leukemia inhibitory factor and brain-derived neurotrophic factor (r=0.361, 0.368, 0.343, p=0.009, 0.007, 0.013, respectively). There was a significant positive correlation between irisin, BDNF, LIF, MSTN and IL 6, and between FGF21 and irisin, MSTN, IL 6 in children (p < 0.05). Conclusions: With the increase in BMI, the risk of metabolic abnormalities in obese children increases. Obese children with one kind of metabolic abnormality are prone to merge with other metabolic abnormalities. The levels of leukemia inhibitory factor, fibroblast growth factor 21, irisin, brain-derived neurotrophic factor, and other myokine in obese children and obese children with abnormal metabolism are different from those in non-obese children and obese children with normal metabolism respectively, and there is interaction between myokines. Presentation: 6/1/2024

8698 Unique populations of pituitary macrophages regulate gonadotropin secretion

Abstract Disclosure: Z. Del Mundo: None. J. Ha: None. A. Zhang: None. K.D. Wiggins: None. G. De Robles: None. C. Garcia: None. N. Ujagar: None. D. Nicholas: None. Chronic inflammation disrupts hormonal balance in the Hypothalamic-Pituitary-Gonadal (HPG) axis, contributing to reproductive disorders. Despite extensive studies on immune cells in the hypothalamus and ovaries, their impact on the pituitary is largely unexplored. Our research reveals that macrophages are the primary immune population in the pituitary during homeostasis. In response to in vivo chronic lipopolysaccharide exposure in mice, a transient macrophage population emerges, associated with reproductive changes, including elevated serum testosterone, prolonged estrous cycle stage, and reduced ovarian antral follicle count. This study aims to characterize pituitary macrophages and elucidate their impact on the HPG axis. We hypothesize that pituitary macrophages change inflammatory status as a response to stimuli and, as a result, modulate gonadotropin secretion. We pinpointed differentially expressed genes (DEGs) in pituitary macrophages using scRNAseq, distinguishing them from other tissue-resident macrophages, including microglia. These DEGs include markers for macrophage activation, phagocytosis, migration, hormone synthesis, and lipid metabolism. Immunohistochemistry validated the distinctive morphology of pituitary macrophages compared to microglia. In vitro depletion of macrophages from mouse pituitaries resulted in decreased pituitary hormone secretion and decreased secretion of G-CSF, IL-9, and CXCL5. These results highlight the role of pituitary macrophages in hormonal regulation, setting the stage for future immunotherapeutic strategies to restore hormonal balance in reproductive disorders. Presentation: 6/3/2024

7551 Association of Remnant Cholesterol with Sarcopenia in Korean Adults: A Nationwide Population-Based Study using Data from the KNHANES

Abstract Disclosure: S. Jang: None. S. Hwang: None. A. Jang: None. K. Kim: None. J. Yu: None. N. Kim: None. H. Yoo: None. J. Seo: None. S. Kim: None. N. Kim: None. S. Baik: None. K. Choi: None. Objectives: Mounting evidences indicate the importance of interplay between skeletal muscle and lipid metabolism. Remnant cholesterol (remnant-C) is considered as one of the principal residual risk factors for atherosclerotic cardiovascular disease (ASCVD) as well as metabolic disorders, but there is limited study about the impact of remnant-C on sarcopenia. Research design and Methods: Data from the Korea National Health and Nutrition Examination Surveys (KNHANES) between 2008 and 2011 was used in this nationwide population-based study. A total of 17,408 participants were enrolled. Subjects were categorized into 4 groups according to the quartile of remnant-C values. We conducted multivariable logistic regression analysis to evaluate the association between remnant-C and muscle mass measured using dual-energy X-ray absorptiometry (DXA). Results: 1,989 participants (11.4%) presented low muscle mass, and there was a sequential increase in the percentage of low muscle mass across remnant-C quartiles (Q1, 5.8%; Q2, 9.9%; Q3, 12.9%; Q4, 17.1%). In the full adjusted model, those in the highest remnant-C quartile group showed the highest odds ratio for low muscle mass after adjusting for various confounding factors (Q2, 1.18 [0.95-1.47]; Q3, 1.12 [0.9-1.39]; Q4, 1.37 [1.1-1.71], P <0.05). A wide range of subgroup and sensitivity analyses showed consistent results, which may support the robustness of the present findings. Conclusions: Increased remnant-C value is related to high risk of low muscle mass in Korean population. Remnant-C may be a novel marker to predict and manage sarcopenia in the aging society. There should be future research to verify its clinical usefulness. Presentation: 6/2/2024

12220 Impaired Esrra-mediated Regulation Of Lysosomal Protein Translation And Autophagy In MASH: Restoration And MASH Reversal By Alternate Day Fasting

Abstract Disclosure: M. Tripathi: None. K. Gauthier: None. R. Sandireddy: None. S. Park: None. V. Giguere: None. P.K. Chow: None. S. Ghosh: None. D.P. McDonnell: None. P.M. Yen: None. B. Singh: None. The regulation of global and specific protein synthesis during the progression of metabolic dysfunction-associated steatohepatitis (MASH) is poorly understood. Accordingly, we performed a comprehensive analyses of protein translation by employing label-free quantitative proteomics, puromycin-labeling, and polysome profiling, and found a reduction in protein synthesis during lipotoxic stress in vitro and in liver tissues from MASH mouse models. We also found that expression of estrogen receptor-related receptor-α(ERRa/Esrra) and ribosomal Rplp1 were significantly downregulated at protein levels. Additionally, Esrra recruitment was decreased on the Rplp1 promoter, and led to diminished Rplp1 mRNA and protein expression. Taken together, these events reduced overall translation activity and the specific translation of lysosomal (e.g.,Lamp2, Ctsd) and autophagy (e.g., Sqstm1, Map1lc3b) proteins during MASH. Moreover, Esrra-Rplp1-mediated translation of these lysosomal and autophagy proteins and autophagy was compromised in MASH patients and liver-specific Esrra-deficient mice. Remarkably, alternate day fasting induced hepatic Esrra expression and reactivated Esrra-Rplp1 signaling in mice with MASH, leading to the re-expression of autophagy and lysosomal proteins to restore autophagy and reduce lipotoxicity, inflammation, and fibrosis. Thus, the Esrra-Rplp1-mediated translation of lysosomal and autophagy proteins critical for preventing lipotoxicity, inflammation, and fibrosis was suppressed during MASH. Reactivation of this pathway by intermittent fasting was able to reverse MASH. Our findings showed that Esrra not only regulated the transcription of genes involved in lipid metabolism, but also the specific translation of autophagy and lysosomal proteins via induction of Rplp1; thus, providing a molecular explanation for the beneficial hepatic effects of alternate day fasting in MASH. Presentation: 6/2/2024

Plasma Proteomics of Type 2 Diabetes, Hypertension, and Co-Existing Diabetes/Hypertension in Thai Adults

The study explored proteomics to better understand the relationship between type 2 diabetes (T2DM) and hypertension (HT) in Thai adults, using shotgun proteomics and bioinformatics analysis. Plasma samples were taken from 61 subjects: 14 healthy subjects (mean age = 40.85 ± 7.12), 13 with T2DM (mean age = 57.38 ± 6.03), 16 with HT (mean age = 66.87 ± 10.09), and 18 with coexisting T2DM/HT (mean age = 58.22 ± 10.65). Proteins were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Protein–protein interactions were analyzed using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) version 11.5. We identified six unique proteins in T2DM patients, including translationally controlled 1 (TPT1) and nibrin (NBN), which are associated with the DNA damage response. In HT patients, seven unique proteins were identified, among them long-chain fatty acid-CoA ligase (ASCL), which functions in the stimulation of triacylglycerol and cholesterol synthesis, and NADPH oxidase activator 1 (NOXA1), which is involved in high blood pressure via angiotensin II-induced reactive oxygen species (ROS)-generating systems. In coexisting T2DM/HT patients, six unique proteins were identified, of which two—microtubule-associated protein 1A (MAP1A)—might be involved in dementia via RhoB-p53 and diacylglycerol kinase beta (DGKB), associated with lipid metabolism. This study identified new candidate proteins that are possibly involved in the pathology of these diseases.

6731 Initial therapeutic effects of weekly growth hormone replacement therapy: somapacitan

Abstract Disclosure: S. Fujio: None. R. Makino: None. J. Sugata: None. T. Hanada: None. R. Hanaya: None. Introduction: In Japan, the restriction on the administration of somapacitan, a long-acting growth hormone (GH) analogue, was lifted in December 2022, allowing the drug to be administered to many patients with severe growth hormone deficiency (sGHD). [Patients and methods] We have 10 patients for whom somapacitan was started as a new drug regime and 26 patients who switched from their daily GH replacement therapy. Among these 36 patients, 21 patients (5 new cases and 16 switched cases) who were followed for more than 6 months after the start of treatment were included in the present study. We compared lipid metabolism, glucose tolerance, liver function, and quality-of-life before and after treatment with somapacitan. [Result] The study population included 12 men and 9 women with a median age of 65 years. Cases included 15 NF-PitNET, 2 Lactotroph PitNET, 2 germ cell tumor, 1 craniopharyngioma, and 1 granuloma. Starting doses of somapacitan were 1.5 mg/week for adults to 60 years of age and 1.0 mg/week for patients aged >60 years. In the switched cases, the median levels of T-chol dropped from 214.5 to 198.5 mg (p<0.05). The median levels of HbA1c dropped from 5.9 to 5.8% (p<0.05). In the newly prescribed cases, the median levels of γ-GTP dramatically improved from 53 to 34I U/L, but this was not statistically significant. In the newly prescribed cases, quality-of-life assessment by Adult Hypopituitarism Questionnaire; AHQ showed improvement in both psychological/social aspects and physical function, but the number of cases was small and no significant difference was obtained. Body fat percentage measured by the impedance method showed no significant change in either the switched or newly prescribed groups. There were no adverse events, but some participants commented that it was easier to forget weekly injections of somapacitan than the daily GH. [Discussion] We were able to introduce somapacitan without any major problems. In newly prescribed cases, somapacitan resulted in a significant improvement in liver function. Improvements in lipid metabolism and glucose tolerance were observed in the switched patients. Compared to the daily GH replacement therapy, somapacitan may have a higher GH replacement effect. Presentation: 6/3/2024

9316 Modulation Of Intracellular Lipid Access By ATGL Determines Ferroptosis Sensitivity In Castration-resistant Prostate Cancer

Abstract Disclosure: P. Cao: None. D. Awad: None. J. Han: None. D.E. Frigo: Grant Recipient; Self; GTx, Inc.. Other; Self; Familial relationship with Biocity Biopharmaceuticals, Hummingbird Bioscience, Bellicum Pharmaceuticals, Maia Biotechnology, Alms Therapeutics, Hinova Pharmaceuticals and Barricade Therapeutics. Ferroptosis induction has recently been recognized as a novel therapeutic approach to alter the outcomes of drug-resistant cancer. Ferroptosis is cell death that is caused by the intracellular accumulation of toxic lipid hydroperoxides. Due to their elevated metabolism, castration-resistant prostate cancer (CRPCs) are highly prone to ferroptosis; yet, many of them manage to avert this cellular fate. We have identified a key enzyme involved in lipid metabolism, adipose triglyceride lipase (ATGL), that engenders CRPCs with the ability to resist ferroptosis. Our data has shown that ATGL deletion by CRISPR-Cas9 knockout method sensitized human CRPC cell lines such as C4-2, C4-2BLT, and PC3 cells to the ferroptosis inducer RSL3. In all cases, RSL3-mediated cell death could be blocked by the antioxidant Ferrostatin-1, confirming ferroptosis as the mechanism of cell death. Knocking out ATGL also augmented the ferroptosis inducer-mediated increase in lipid peroxides as indicated by the increased ratio of oxidized to non-oxidized C11-BODIPY 581/591. With regards to the mechanism for the sensitivity of ATGL KO to ferroptosis induction, previous research has established that the enzyme long-chain acyl-CoA synthetase 4 (ACSL4) is universally essential to facilitate ferroptosis. More specifically, ATGL(PNPLA2) was found to inversely correlate with ACSL4 in the Taylor et al., the TCGA PanCancer Atlas, and Metastatic Prostate Adenocarcinoma (SU2C/PCF Dream Team) datasets in both primary and metastatic tumors. qPCR and western blot analysis of ACSL4 levels further showed that ACSL4 expression is closely tied to the lipase activity of ATGL. Addition of arachidonic acid significantly induced ferroptosis when combined with RSL3 in a dose-dependent manner only in ATGL KO cells. This indicates that PUFAs can render ATGL KO cells even more sensitive to RSL3-induced ferroptosis while cells with functional ATGL remain highly resistant, further reinforcing that ATGL is an essential safeguard of CRPC against ferroptosis. ATGL KO cells also demonstrated sensitivity to the antiandrogen Enzalutamide. The combination of Enzalutamide and RSL3 substantially decreased cell viability in ATGL KO cells as compared to control cells, indicating a strong synergy effect particularly seen in ATGL KO cells. In summary, this work demonstrates that ATGL is an important and novel regulator of ferroptosis in CRPC and supports the use of ferroptosis inducer as a new therapeutic approach in CRPC. Presentation: 6/2/2024

7086 Disrupted Mitochondrial Function in Alström Syndrome- A Monogenic Model of Insulin Resistance and Obesity

Abstract Disclosure: S. Ali: None. S. Heising: None. V. Veeranna: None. A. Vincent: None. G.S. Xavier: None. T. Geberhiwot: None. Alström syndrome (ALMS) is a rare monogenic disease typified by severe insulin resistance (IR) and obesity. IR and obesity are cardinal features of metabolic syndrome. The metabolic effects of insulin at key target tissues leads to metabolic haemostasis by promoting glucose and lipid uptake and metabolism to generate energy in cells. Although insulin is a major regulator of fuel metabolism, its effects on mitochondrial ATP production in severe insulin resistance are unclear. RNASeq data from adipose tissue (AT) from patients with ALMS show downregulation of the expression of genes associated with mitochondrial respiratory chain function, pointing towards possible altered mitochondrial function in ALMS. We therefore undertook a detailed assessment of mitochondrial oxidative phosphorylation capacity (OXPHOS) in skeletal muscle (SM) in ALMS. We performed SM biopsy in 10 ALMS and 10 healthy control volunteers that were age, gender and Body Mass Index matched. The SM was subjected to high resolution respirometry, the gold standard method to quantify mitochondrial function ex vivo, using OROBOROS Oxygraph -2k (O2k) system. Overall OXPHOS was higher in control SM compared to ALMS, with maximal respiration of 62.96±19.2 and 44.24 ± 12.53 pmol/(s*mg), respectively (p<0.05).Reduced oxygen influx was observed in ALMS SM in comparison to controls for fatty acid ß oxidation (6.7±5.96 vs 7.87±2.7 pmol/(s*mg);p<0.05, at complex I (19.4 ± 8.98 vs 29.7 ±5.3 pmol/(s*mg);p<0.05, and at complex II (34.98 ±11.75 vs 53.52± 13.2 pmol/(s*mg) ;p<0.05. Mitochondrial membrane integrity was unaffected during these experiments. Therefore, our analysis unveils a consistent reduction in mitochondrial respiration across all the electron transport pathway. This noteworthy finding suggests impairment in respiratory function and the electron transport chain in mitochondria, a crucial aspect of cellular energy metabolism. Several studies have previously linked IR with mitochondrial dysfunction, where insulin-resistant rodents and humans have shown blunted mitochondrial response to ATP generation. Our results align with this body of evidence emphasizing the significance of investigating the underlying mechanism contributing to this phenomenon. These findings could pave the way to exploring potential mitochondrial-targeted therapies to restore mitochondrial function and therefore, improve insulin sensitivity to tackle IR in ALMS. Presentation: 6/2/2024

12248 Leptin Signaling Deficiency At The Central Nervous System Reduces Hepatic Glucagon Sensibility Disturbing Liver Amino Acid Metabolism Leading To Hyperaminoacidemia And Hyperglucagonemia In Male Adult Rats

Abstract Disclosure: C. Pintado Losa: None. L. Mazuecos Fernández-Pacheco: None. Ó. Gómez Torres: None. S. Artigas Jerónimo: None. E. Burgos Ramos: None. I. Ramos: None. J. Poveda Colado: None. C. Arribas Mocoroa: None. A. Andres: None. N. Gallardo: None. Leptin regulates glucagon secretion, but the contribution of central leptin resistance to circulating glucagon levels and hepatic glucagon signaling is poorly studied. To analyze the effects of deficient hypothalamic leptin signaling on glucagon levels and hepatic glucagon signaling, we infused intracerebroventricularly a rat-specific leptin receptor antagonist SLA (0,2 µg/day) for 21 days to male 3-month-old Wistar rats (n=12) or PBS (n=12). At day 21 of treatment and 30 min before sacrifice, a glucagon challenge (100 µg/kg) was performed in 16h fasted rats. After sacrifice, blood and liver samples were collected for analysis. Serum hormones, urea, and total and branched-chain amino acids (BCAA) levels were determined using commercial kits and by RP-HPLC. Hepatic neutral lipid was extracted and quantified using an enzymatic kit and the hepatic content of mRNA and proteins involved in lipid and amino acid metabolism were measured by RT-PCR and Western-Blot. Additionally, the HOMA-IR and glucagon-alanine index were determined in all rats. Blocking central leptin signaling led to impaired fat oxidation and triglyceride export capacity in the liver, resulting in a 50% increase in hepatic triglyceride content in SLA-treated rats. Glucagonemia increased in SLA-treated rats, indicating impaired hepatic glucagon sensitivity. In fact, in response to exogenous glucagon, the hepatic phosphorylation of CREB was reduced by 55% in SLA-infused compared to control rats. Importantly, SLA treatment significantly decreases the expression and the activity of BCKDH (branched-chain alpha-keto acid dehydrogenase) in the liver, leading to a reduction in the BCAA degradation in SLA-treated rats, hyperaminoacidemia, and decreased serum urea levels. In conclusion, deficient hypothalamic leptin signaling alters glucose, lipid, and amino acid homeostasis, highlighting the relevance of central leptin action in the control of peripheral metabolism and glucagon sensitivity. Funding: Work supported by Ministerio de Ciencia, Innovación y Universidades under project grants RTI2018-098643-B-I00, PID2021-128243OB-I00, and from the University of Castilla-La Mancha and the European Regional Development Fund (FEDER) under project grant 2023- GRIN-34280. Presentation: 6/1/2024

The mitigating role of lysophospholipids in hepatic lipid metabolism and intestinal immunity in juvenile black seabream (Acanthopagrus schlegelii) fed a high-fat diet

An 8-week feeding experiment investigated the effects of lysophospholipids (LP) on growth performance, hepatic lipid metabolism, intestinal immunity and antioxidation in juvenile black seabream (Acanthopagrus schlegelii) (initial weight 4.60 ± 0.01 g) on a high-fat diet. Five experimental diets were established: normal fat diet (13 %, CON), high-fat diet (18 %, HFD) and HFD with different levels of LP (0.05 %, 0.1 %, and 0.2 %). The results indicated that dietary LP had no impact on the specific growth rate and survival rate of juvenile black seabream (P > 0.05), while 0.2 %LP supplementation reduced the intraperitoneal fat ratio (IPF) (P < 0.05). Dietary 0.1 % and 0.2 %LP supplementation reduced the total lipid content and the size and number of lipid droplets in the liver (P < 0.05). The diets supplemented with LP reduced the contents of TG and LDL-C in the serum (P < 0.05), without affecting T-CHO and HDL-C (P > 0.05). The expression of lipid transport genes including apoa, apob, fatp1, and fatp4, were markedly up-regulated with increased dietary LP supplementation (P < 0.05). Moreover, dietary 0.2 %LP supplementation notably increased mRNA expression levels of scarb1, ffar3, acsl5 and glp-1 in the intestine (P < 0.05). Dietary LP notably down-regulated the mRNA expression of genes related to the lipogenesis pathway including fas, aco and srebp-1c, while up-regulating mRNA expression of lipogenesis-related genes including cpt1α, lpl, and pparα (P < 0.05). Additionally, dietary 0.2 %LP supplementation notably increased total antioxidant capacity in the intestine and up-regulated expression levels of intestinal antioxidant genes, including mn sod, cu-zn sod, gpx, and cat (P < 0.05), fish fed diets with 0.2 %LP down-regulation of pro-inflammatory genes, including tnfα and nf-κb, and up-regulation of anti-inflammatory factors, tgfβ-1, il-10 and tight-junction protein genes including (oclna, cldni, cldn3, and tjp1b) in the intestine (P < 0.05). In conclusion, dietary LP improved intestinal fatty acid transport and liver lipolysis, alleviating intestinal oxidative damage and inflammatory reactions caused by HFD in black seabream.

8359 Increased hepatic SGK1 activity promotes metabolic dysfunction-associated fatty liver disease in a sex-dependent manner

Abstract Disclosure: A. Vastola-Mascolo: None. G. Hernández: None. D. Alvarez de la Rosa: None. The serum and glucocorticoid-induced kinase 1 (SGK1) is a Ser/Thr kinase with key roles in fluid and electrolyte homeostasis, blood pressure regulation and energy metabolism. Its expression is controlled by steroid hormones such as glucocorticoids, mineralocorticoids and estrogen, in addition to other stimuli such as glucose. SGK1 activation mainly depends on the PI3 kinase pathway, implicating it in insulin signaling. Previous work from our laboratory demonstrated that a systemic increase in SGK1 activity exacerbates diet-induced development of metabolic syndrome in mouse, characterized by obesity, glucose intolerance, insulin resistance, dyslipidemia and hypertension. In addition, a high-fat diet rapidly led to the development of hepatic steatosis. We now test the hypothesis that at least part of the effects of increased systemic SGK1 activity promoting the development of metabolic syndrome are due to alterations in liver glucose or lipid handling. To that end we developed a mouse strain with hepatocyte-specific transgenic SKG1 expression and challenged it with high-fat or high-fat/high-sucrose diets. Our results show sex differences in the development of obesity, with a marked increase in body weight in female, but not male transgenic animals. Glucose homeostasis was normal in both sexes. Increased obesity in females correlated with increased lipid accumulation in the liver. However, liver fibrosis, inflammation and dyslipidemia were more marked in male animals, further suggesting an interaction between SGK1 and sex steroid hormone signaling. Our results demonstrate a key role of SGK1 in liver lipid metabolism and suggest a crosstalk between this signaling pathway and sex hormones, which determine a more negative outcome in male animals. Presentation: 6/1/2024

8308 Up-regulation of Diacylglycerol kinase gamma (DGKG) in aggressive recurrent pituitary tumors could be targeted by Dasatinib reducing cell proliferation and induced apoptosis

Abstract Disclosure: K. Taniguchi-Ponciano: None. I. Remba: None. M. Loza-Mejia: None. J. Salazar: None. A. Mendez-Perez: None. C. Aguilar-Flores: None. A. Chavez-Gonzalez: None. E. Ortiz-Reyes: None. L. Bonifaz: None. D. Marrero-Rodríguez: None. M. Mercado: None. Pituitary tumors (PT) represent 15% of all intracranial tumors. Some PTs exhibit an aggressive behavior, growing rapidly and invading surrounding tissues, and are frequently resistant to multimodal treatment showing multiple recurrences. Pituitary tumors often recur after initial surgery, particularly when invasive, precluding complete resection of the lesion, which can only be achieved in ∼40-50% of all patients.We have previously characterized transcriptome and exome from 22 tumor lesions from 11 patients by RNA- and DNAseq and methylome profile by microarrays of aggressive, both primary and recurrent PT from the same patient to identify molecular pharmacological targets.Among the differentially expressed genes in most recurrent tumors we found those related to fatty acid biosynthesis and metabolism, phosphatidylinositol, glycerophospholipid and phospholipase D signaling. Importantly, one gene found in most of the lipid-related pathways was diacylglycerol kinase gamma (DGKG). DGKG gene expression was confirmed by immunofluorescence and did not seem to be regulated by DNA methylation. And DGKG showed allelic c.G947A:p.R316K variant in all primary and recurrent tumor tissues analyzed, more research is needed to understand genetic variant impact on protein function. We then performed DGKG molecular docking for FDA-approved drug repurposing. Human DGKG tridimensional model was downloaded from AlphaFold and Autodock Vina, Molegro Virtual Docker, PyMol v2.5.2 program and the Protein-Ligand Interaction Profiler web tool were used. The in silico ADMET profiles were generated in ADMETLab 2.0 using only FDA approved drugs. We identified Dasatinib as a strong candidate for DGKG targeting. We then exposed GH3 cell line to increasing concentrations of Dasatinib (1, 2.5 y 5 μM) using DMSO as vehicle. After cell viability was assessed, approximatively 31% of all live GH3 cells were at proliferative state without any treatment, that was taken as our basal quantity to compare the GH3 cells treated with the TKI’s. Dasatinib reduced approximatively 28% the cell proliferation at 1 μM (p=0.0048), at 2.5 μM reduced nearly 50% of cell proliferation (p=0.003) and at 5 μM inhibited nearly 98% of cell proliferation (p=0.0395) by means of Click-iT EdU Cell proliferation Kit. We then, evaluated Dasatinib apoptosis induction capacity. Interestingly, the 1 μM Dasatinib concentration induced apoptosis (p=0.0001) as concentrations increased, cell death also increased considerably (p=0.0001) measured by Anexin V-FITC and DAPI assay. The RNAseq data from GH3 cells exposed to Dasatinib show diminished gene expression of cell cycle related genes and glycolysis.In conclusion, we observed DGKG upregulated in recurrent aggressive pituitary tumors participating in lipid metabolism pathways and could be targeted by Dasatinib at very low doses. Presentation: 6/3/2024

Unravelling the molecular mechanism underlying drought stress tolerance in Dinanath (Pennisetum pedicellatum Trin.) grass via integrated transcriptomic and metabolomic analyses

Dinanath grass (Pennisetum pedicellatum Trin.) is an extensively grown forage grass known for its significant drought resilience. In order to comprehensively grasp the adaptive mechanism of Dinanath grass in response to water deficient conditions, transcriptomic and metabolomics were applied in the leaves of Dinanath grass exposed to two distinct drought intensities (48-hour and 96-hour). Transcriptomic analysis of Dinanath grass leaves revealed that a total of 218 and 704 genes were differentially expressed under 48- and 96-hour drought conditions, respectively. The genes that were expressed differently (DEGs) and the metabolites that accumulated in response to 48-hour drought stress mainly showed enrichment in the biosynthesis of secondary metabolites, particularly phenolics and flavonoids. Conversely, under 96-hour drought conditions, the enriched pathways predominantly involved lipid metabolism, specifically sterol lipids. In particular, phenylpropanoid pathway and brassinosteroid signaling played a crucial role in drought response to 48- and 96-hour water deficit conditions, respectively. This variation in drought response indicates that the adaptation mechanism in Dinanath grass is highly dependent on the intensity of drought stress. In addition, different genes associated with phenylpropanoid and fatty acid biosynthesis, as well as signal transduction pathways namely phenylalanine ammonia-lyase, putrescine hydroxycinnamoyl transferase, abscisic acid 8’-hydroxylase 2, syntaxin-61, lipoxygenase 5, calcium-dependent protein kinase and phospholipase D alpha one, positively regulated with drought tolerance. Combined transcriptomic and metabolomic analyses highlights the outstanding involvement of regulatory pathways related to secondary cell wall thickening and lignin biosynthesis in imparting drought tolerance to Dinanath grass leaves. These findings collectively contribute to an enhanced understanding of candidate genes and key metabolites relevant to drought response in Dinanath grass. Furthermore, they establish a groundwork for the creation of a transcriptome database aimed at developing abiotic stress-tolerant grasses and major crop varieties through both transgenic and genome editing approaches.

5045 The Effects Of Non-functioning Adrenal Incidentalomas On Metabolic Comorbidities And Clinical Characteristics Changes: A Systematic Review And Meta-Analysis

Abstract Disclosure: X. Li: None. H. Lan: None. J. Wen: None. G. Chen: None. W. Lin: None. The Effects of Non-functioning Adrenal Incidentalomas on Metabolic Comorbidities and Clinical Characteristics Changes: A Systematic Review and Meta-analysis. Context: Adrenal incidentalomas (AI) are frequently detected during abdominal imaging, with non-functioning adrenal incidentalomas (NFAI) being particularly common, even in elderly individuals. This meta-analysis investigates the influence of NFAI on metabolic comorbidities, comparing non-surgical and surgical patient groups, and assessing alterations in NFAI characteristics. Design: Our comprehensive meta-analysis utilized data from multiple databases, encompassing studies from January 2000 to August 21, 2023.Setting: Data sources included PubMed, Embase, Cochrane Library, and Web of Science. Participants: The analysis comprises 24 articles involving 2,770 NFAI patients, categorized into non-surgical and surgical groups. Intervention: The non-surgical group underwent no surgery, while the surgical group underwent tumor resection. Main Outcome Measure: The study investigated changes in metabolic comorbidities (hypertension, diabetes, obesity, lipid metabolism disorders), tumor characteristics, and hormone production in NFAI patients during follow-up or after surgery. Results: In the non-surgical NFAI patient group (20 studies), metabolic comorbidities exhibited a discernible upward trajectory during follow-up. The initial hypertension prevalence of 58.3% increased by 4.2% over a 4-5 year follow-up period. Moreover, diabetes, obesity, and lipid metabolism disorders experienced significant increases of 5.8%, 2.2%, and 8.8%, respectively. In contrast, the surgical group (6 studies) demonstrated a notable reduction in hypertension, with 43.9% of initially hypertensive patients achieving hypertension-free status after surgery. As for tumor changes in the non-surgical group, they were generally inconsequential, with only 5% of patients witnessing tumor growth exceeding 10mm over approximately 3.3 years, and 8% undergoing functional changes. These findings underscore the divergent impact of non-surgical and surgical interventions on metabolic comorbidities in NFAI patients. Conclusion: The study advocates for regular monitoring of blood glucose and blood pressure in NFAI patients, especially those with metabolic comorbidities. When necessary, adenoma resection should be considered. Further investigation is warranted to elucidate the mechanisms connecting NFAI with metabolic factors. Presentation: 6/1/2024

Qiwei Jinggan Ling regulates oxidative stress and lipid metabolism in alcoholic liver disease by activating AMPK

BackgroundAlcoholic liver disease (ALD) is a severe public health concern worldwide and there is still a lack of effective treatments. Qiwei Jinggan Ling (QJL) has protective effects against various liver injuries, but its pharmacological action on ALD has received little attention. PurposeTo investigate the effect and mechanism of QJL on ALD in vivo and in vitro. MethodsIn vivo, an ALD mouse model was established by alcohol combined with a high-fat diet (HFD) and treated with QJL. Biochemical indicators, HE staining, and Oil Red O staining were employed to assess hepatic oxidative stress, steatosis, and alcohol metabolism. RNA sequencing analysis was performed, and the results were verified by qRT-PCR and Western blot to elucidate the hepatoprotective mechanism of QJL. In vitro, HepG2 cells were co-stimulated with NaOA (sodium oleate) and EtOH (ethanol), followed by intervention with Compound C (CC, AMPK inhibitor) and QJL-containing serum. Oil Red O, BODIPY (boron-dipyrromethene), and ROS (reactive oxygen species) staining were applied to validate the efficacy and mechanism of QJL-containing serum. The expression of AMP-activated protein kinase (AMPK) pathway-related factors was analyzed through qRT-PCR and Western blot for additional corroboration. Moreover, the key pharmacodynamic components of QJL were identified by UPLC-MS/MS and molecular docking. ResultsIn vivo, QJL ameliorated liver structural disorders, steatosis, oxidative stress, and impaired alcohol metabolism, as indicated by biochemical indicators and histopathological assays. RNA sequencing analysis revealed that QJL reversed the expression of genes related to alcohol metabolism, fatty acid metabolism, and cholesterol metabolism. The results of qRT-PCR and Western blot were in line with those of RNA sequencing. Furthermore, it was discovered that QJL significantly upregulated the expression of p-AMPK and downregulated the expression of sterol regulatory element binding transcription factor 1 (SREBP-1c). In vitro, biochemical indicators and staining assays demonstrated that QJL-containing serum inhibited lipid accumulation and oxidative stress. The qRT-PCR and Western blot analysis revealed that QJL-containing serum markedly enhanced the expression of p-AMPK and carnitine palmitoyltransferase 1a (Cpt1a), while suppressing the expression of SREBP-1c, fatty acid synthase (Fasn), and acetyl-coenzyme A carboxylase 1 (ACC-1). However, CC inhibited the above pharmacological activities of QJL-containing serum. Additionally, (2S)-Liquiritigenin, Glycyrrhetinate, Isovitexin, Taxifolin, and Yohimbine were proved to be the key active components of QJL. ConclusionQJL had the potential to be a therapeutic drug for ALD by activating the AMPK pathway, thereby regulating lipid metabolism and inhibiting oxidative stress.