Lipidomic Profiling Research Articles

Association of serum lipidomic profiles with risk of intracranial aneurysm: A Mendelian randomization study.

A two-sample Mendelian randomization (MR) analysis was utilized to assess the causal relationship between lipidomic profiles and the risk of intracranial aneurysms (IAs). Genetic variants related to lipidomic profiles (227 components) and IA [IA, aneurysmal subarachnoid hemorrhage (aSAH) only, unruptured IA (uIA) only] were obtained from published genome-wide association studies (GWASs) or the IEU Open GWAS project and used as instrumental variables for MR analysis. The inverse-variance weighted method was used in the primary analyses to derive causality estimates and was expressed as odds ratio (OR) with 95% confidence interval (CI). Of these 227 lipidomic profiles, only genetically predicted high levels of cholesterol to total lipids ratio in very small very-low-density lipoproteins (VLDL) [OR = 0.629 (95% CI, 0.504-0.786)], cholesteryl esters to total lipids ratio in very small VLDL [OR = 0.637 (95% CI, 0.509-0.797)], ratio of docosahexaenoic acid to total fatty acids [OR = 0.691 (95% CI, 0.582-0.820)], and ratio of polyunsaturated fatty acids to monounsaturated fatty acids [OR = 0.630 (95% CI, 0.522-0.760)] reduced the risk of aSAH, whereas genetically predicted high ratio of monounsaturated fatty acids to total fatty acids [OR = 1.471 (95% CI, 1.215-1.781)] increased the risk of aSAH. Moreover, genetically predicted high levels of cholesterol to total lipids ratio in very small VLDL [OR = 0.657 (95% CI, 0.542-0.798)], cholesteryl esters to total lipids ratio in very small VLDL [OR = 0.663 (95% CI, 0.548-0.803)], free cholesterol to total lipids ratio in small VLDL [OR = 0.682 (95% CI, 0.560-0.832)], phospholipids to total lipids ratio in small VLDL [OR = 0.674 (95% CI, 0.548-0.830)], and ratio of polyunsaturated fatty acids to monounsaturated fatty acids [OR = 0.678 (95% CI, 0.569-0.808)] reduced the risk of IA. The results of multivariable MR demonstrated that these causal associations persisted after adjusting for systolic blood pressure and cigarettes smoked per day. The effect of serum lipids on IA and aSAH may be mainly caused by subclasses of lipids such as VLDL.

Plasma Lipidomic Profiles Improve upon Traditional Risk Factors for the Prediction of Arterial Stiffness Among Patients with Type 2 Diabetes Mellitum: A Randomized, Placebo-Controlled Trial

Background: Exercise or vitamin D intervention can reduce the risk of arterial stiffness; however, the underlying mechanisms of lipid metabolism remain unexplored. To examine the effects of a 12-week moderate and vigorous exercise program (65–80% maximal heart rate, 60 min/time, 2~3 times/week) with or without vitamin D supplementation (1000 IU/day) on the reduction in arterial stiffness and further explore whether the effects of interventions could be associated with the basal lipidome among patients with Type 2 diabetes mellitum (T2DM). Method: 61 patients with T2DM were randomly assigned to the following groups: control (CON, n = 15), exercise (EX, n = 14), vitamin D (VD, n = 16), and exercise + vitamin D (EX + VD, n = 16). Arterial stiffness risk factors (ankle–brachial index (ABI); brachial–ankle pulse wave velocity (baPWV), systolic blood pressure (SBP), and diastolic blood pressure (DBP)) were evaluated before and after the intervention. The plasma lipidome was determined using ultra-performance liquid chromatography coupled with tandem mass spectrometry. Machine learning was applied to establish prediction models for the responsiveness to arterial stiffness. Result: Vitamin D supplementation could inhibit the decrease in the ankle–brachial index (mean ± SD: EX + VD and VD, −0.001 ± 0.058; EX + CON, −0.047 ± −0.089; p = 0.03). We observed high inter-individual variability in the arterial stiffness risk factors in response to the interventions. We also found that optimally selecting the lipid predictors at baseline, such as SM d44:6, LPE 18:2, and Hex2Cer 29:0, could enhance the predictive power by 100% for arm SBP changes in the exercise group. Basal levels of Cer (33:1) and GM3 (44:4) could enhance the predictive power by 100% for changes in baPWV in the vitamin D group. Conclusions: A 12-week vitamin D supplementation was beneficial in preventing arterial stiffness. Compared with traditional clinical risk factors, specific lipids at baseline could significantly improve the ability to predict intervention-induced changes in the reduction of arterial stiffness.

PTPRZ1 dephosphorylates and stabilizes RNF26 to reduce the efficacy of TKIs and PD-1 blockade in ccRCC.

Clear cell renal cell carcinoma (ccRCC), the most common subtype of renal cell carcinoma, often exhibits resistance to tyrosine kinase inhibitors (TKIs) when used as monotherapy. However, the integration of PD-1 blockade with TKIs has significantly improved patient survival, making it a leading therapeutic strategy for ccRCC. Despite these advancements, the efficacy of this combined therapy remains suboptimal, necessitating a deeper understanding of the underlying regulatory mechanisms. Through comprehensive analyses, including mass spectrometry, RNA sequencing, lipidomic profiling, immunohistochemical staining, and ex vivo experiments, we explored the interaction between PTPRZ1 and RNF26 and its impact on ccRCC cell behavior. Our results revealed a unique interaction where PTPRZ1 stabilized RNF26 protein expression by dephosphorylating it at the Y432 site. The modulation of RNF26 levels by PTPRZ1 was found to be mediated through the proteasome pathway. Additionally, PTPRZ1, via its interaction with RNF26, activated the TNF/NF-κB signaling pathway, thereby promoting cell proliferation, angiogenesis, and lipid metabolism in ccRCC cells. Importantly, inhibiting PTPRZ1 enhanced the sensitivity of ccRCC to TKIs and PD-1 blockade, an effect that was attenuated when RNF26 was simultaneously knocked down. These findings highlight the critical role of the PTPRZ1-RNF26 axis in ccRCC and suggest that combining PTPRZ1 inhibitors with current TKIs and PD-1 blockade therapies could significantly improve treatment outcomes for ccRCC patients.

Lipidomic profiling of serum and liver tissue reveals hepatoprotective mechanism of taxifolin in rats with CCl4-induced subacute hepatic injury based on LC-MS/MS

Currently, the hepatoprotective activity of taxifolin, a flavonoid isolated from Pseudotsuga taxifolia, has been reported in many animal models. However, whether the protective effect of taxifolin on the liver is related to its effect on lipidomics is unclear. Based on the significant therapeutic effect of taxifolin on CCl4 induced subacute hepatic injury, we observed the intervention of taxifolin by lipidomics. The results demonstrate that taxifolin can effectively reverse the damage caused by CCl4, which including hepatocyte vacuolization and necrosis. Lipomic profiling based on liquid chromatography-mass spectrometry showed that taxifolin was able to restore lipidomic changes caused by CCl4, including the levels of lysophosphatidylserine (LPS), phosphatidylcholine (PC), coenzyme (Co), phosphatidylglyceride (PG), phosphatidylserine (PS), dimethylphosphatidylethanolamine (dMePE), ceramide (Cer), sphingosine (So), triglycerides (TG), and monogalactosyl diacylglycerol (MGDG) in the rat liver, and phosphatidylcarbinol (PMe) and phosphatidylethanolamine (PE), plant sphingosine (phSM), glucose ceramide (CerG1), TG, and diglycerides (DG) in serum. Spearman's correlation analysis showed that CerG1, phSM, PE, and PMe in serum, and Cer, dMePE, PG, PS, So, TG, and MGDG in liver were positively correlated with serum levels of aspartate transaminase, alanine transaminase, and liver index; while TG, DG in serum, and Co, LPS, PC in liver were negatively correlated with the parameters. In total, 43 and 34 lipid molecules were altered by taxifolin treatment in the liver and serum, respectively, mainly including glycerophosphoglycerols, glycerophosphocholines, glycerophosphoethanolamines, and linoleic acids and derivatives. Our findings help to provide novel insights into the mechanism of the hepatoprotective effect of taxifolin from a lipidomics approach.

Healthy plasma lipidomic signatures depend on sex, age, body mass index, and contraceptives but not perceived stress.

Perceived stress is thought to contribute to the pathogenesis of metabolic, vascular, mental, and immune diseases, with different susceptibilities in women and men. The present study investigated if and how perceived stress and/or demographic variables including sex, age, body mass index, regular prescription drugs, occasional analgesics, or dietary supplements manifested in plasma lipidomic profiles, obtained by targeted and untargeted mass spectrometry analyses. The study included 217 healthy women and 108 healthy men, aged 18-68 years, who were recruited in a 2:1 female:male ratio to account for women with/without contraceptives. As expected, dehydroepiandrosterone sulfate (DHEAS) and ceramides were higher in men than women, and DHEAS decreased with age, while ceramides increased. Contrary to expectations, neither DHEAS nor ceramides were associated with perceived stress (PSQ30 questionnaire), which was however, associated with BMI in men, but not in women. None of the lipid species or classes showed a similar "age X sex X BMI" interaction, but the endocannabinoid palmitoylethanolamide (PEA) correlated with BMI and hypertension. Independent of perceived stress, lysophosphatidylcholines (LPCs) were lower in women than men, whereas LPC metabolites, lysophosphatidic acids (LPAs), were higher in women. The LPA:LPC ratio was particularly high in women using oral contraceptives suggesting a strong hormone-induced extracellular conversion of LPCs to LPAs, which is catalyzed by the phospholipase D, autotaxin. The results reveal complex sex differences in perceived stress and lipidomic profiles, the latter being exacerbated by contraceptive use, but perceived stress and lipids were not directly correlated.

Bioactive Lipids in Dunaliella salina: Implications for Functional Foods and Health.

Dunaliella salina is a green microalga extensively explored for β-carotene production, while knowledge of its lipid composition is still limited and poorly investigated. Among lipids, polar lipids have been highlighted as bioactive phytochemicals with health-promoting properties. This research aimed to provide an in-depth lipidome profiling of D. salina using liquid and gas chromatography coupled with mass spectrometry. The lipid content was 6.8%, including phospholipids, glycolipids, betaine lipids, sphingolipids, triglycerides, diglycerides, and pigments. Among the total esterified fatty acids, 13.6% were 18:3 omega-3 and 14.7% were 18:1 omega-9. The lipid extract of D. salina showed anti-inflammatory activity by inhibiting cyclooxygenase-2 activity at 100 µg/mL, dose-dependent antioxidant scavenging activity, and antidiabetic activity by inhibiting α-glucosidase activity at 25 and 125 µg/mL. In conclusion, the lipid extract of D. salina has the potential to be used as a functional food ingredient or in the nutraceutical and cosmeceutical industries.

MASLD in persons with HIV is associated with high cardiometabolic risk as evidenced by altered advanced lipoprotein profiles and targeted metabolomics

BackgroundMetabolic dysfunction associated steatotic liver disease (MASLD) is associated with increased cardiovascular disease (CVD) risk in persons with HIV (PWH). The lipidomic and metabolomic alterations contributing to this risk are poorly understood. We aimed to characterize the advanced lipoprotein and targeted metabolomic profiles in PWH and assess if the presence and severity of MASLD influence these profiles.MethodsThis is a cross-sectional analysis of a prospectively enrolled multicenter cohort. PWH without alcohol abuse or known liver disease underwent vibration-controlled transient elastography for controlled attenuation parameter (CAP) and liver stiffness measurement (LSM). Lipidomic and metabolomic profiling was undertaken with nuclear magnetic resonance (NMR) spectroscopy. Hepatic steatosis was defined as CAP ≥ 263 dB/m and clinically significant fibrosis (CSF) as LSM ≥ 8 kPa. Logistic regression models assessed associations between MASLD, CSF and lipidomic and metabolic parameters.ResultsOf 190 participants (71% cisgender male, 96% on antiretroviral therapy), 58% had MASLD and 12% CSF. Mean (SD) age was 48.9 (12.1) years and body mass index (BMI) 29.9 (6.4) kg/m2. Compared to PWH without MASLD (controls), PWH with MASLD had lower HDL-C but higher total triglyceride, VLDL-C, branched-chain amino acids, GlycA, trimethylamine N-oxide levels, Lipoprotein-Insulin Resistance and Diabetes Risk Indices. There were no significant differences in these parameters between participants with MASLD with or without CSF. In a multivariable regression analysis, MASLD was independently associated with changes in most of these parameters after adjustment for age, gender, race/ethnicity, type 2 diabetes mellitus, BMI, and lipid lowering medications use.ConclusionsMASLD in PWH is independently associated with altered advanced lipoprotein and targeted metabolic profiles, indicating a higher CVD risk in this population.

Impact of soluble epoxide hydrolase inhibition on silica-induced pulmonary fibrosis, ectopic lymphoid neogenesis, and autoantibody production in lupus-prone mice

Objective Acute intranasal (IN) instillation of lupus-prone NZBWF1 mice with crystalline silica (cSiO2) triggers robust lung inflammation that drives autoimmunity. Prior studies in other preclinical models show that soluble epoxide hydrolase (sEH) inhibition upregulates pro-resolving lipid metabolites that are protective against pulmonary inflammation. Herein, we assessed in NZBWF1 mice how acute IN cSiO2 exposure with or without the selective sEH inhibitor TPPU influences lipidomic, transcriptomic, proteomic, and histopathological biomarkers of inflammation, fibrosis, and autoimmunity. Methods Female 6-week-old NZBWF1 mice were fed control or TPPU-supplemented diets for 2 weeks then IN instilled with 2.5 mg cSiO2 or saline vehicle. Cohorts were terminated at 7 or 28 days post-cSiO2 instillation (PI) and lungs analyzed for prostaglandins, cytokines/chemokines, gene expression, differential cell counts, histopathology, and autoantibodies. Results cSiO2-treatment induced prostaglandins, cytokines/chemokine, proinflammatory gene expression, CD206+ monocytes, Ly6B.2+ neutrophils, CD3+ T cells, CD45R+ B cells, centriacinar inflammation, collagen deposition, ectopic lymphoid structure neogenesis, and autoantibodies. While TPPU effectively inhibited sEH as reflected by skewed lipidomic profile in lung and decreased cSiO2-induced monocytes, neutrophils, and lymphocytes in lung lavage fluid, it did not significantly impact other biomarkers. Discussion cSiO2 evoked robust pulmonary inflammation and fibrosis in NZBWF1 mice that was evident at 7 days PI and progressed to ELS development and autoimmunity by 28 days PI. sEH inhibition by TPPU modestly suppressed cSiO2-induced cellularity changes and pulmonary fibrosis. However, TPPU did not affect ELS formation or autoantibody responses, suggesting sEH minimally impacts cSiO2-triggered lung inflammation, fibrosis, and early autoimmunity in our model.

Plasma lipidomic signatures of dementia with Lewy bodies revealed by machine learning, and compared to alzheimer's disease

BackgroundDementia with Lewy Bodies (DLB) is a complex neurodegenerative disorder that often overlaps clinically with Alzheimer’s disease (AD), presenting challenges in accurate diagnosis and underscoring the need for novel biomarkers. Lipidomic emerges as a promising avenue for uncovering disease-specific metabolic alterations and potential biomarkers, particularly as the lipidomics landscape of DLB has not been previously explored. We aim to identify potential diagnostic biomarkers and elucidate the disease's pathophysiological mechanisms.MethodsThis study conducted a lipidomic analysis of plasma samples from patients with DLB, AD, and healthy controls (HCs) at Xuanwu Hospital. Untargeted plasma lipidomic profiling was conducted via liquid chromatography coupled with mass spectrometry. Machine learning methods were employed to discern lipidomic signatures specific to DLB and to differentiate it from AD.ResultsThe study enrolled 159 participants, including 57 with AD, 48 with DLB, and 54 HCs. Significant differences in lipid profiles were observed between the DLB and HC groups, particularly in the classes of sphingolipids and phospholipids. A total of 55 differentially expressed lipid species were identified between DLB and HCs, and 17 between DLB and AD. Correlations were observed linking these lipidomic profiles to clinical parameters like Unified Parkinson’s Disease Rating Scale III (UPDRS III) and cognitive scores. Machine learning models demonstrated to be highly effective in distinguishing DLB from both HCs and AD, achieving substantial accuracy through the utilization of specific lipidomic signatures. These include PC(15:0_18:2), PC(15:0_20:5), and SPH(d16:0) for differentiation between DLB and HCs; and a panel includes 13 lipid molecules: four PCs, two PEs, three SPHs, two Cers, and two Hex1Cers for distinguishing DLB from AD.ConclusionsThis study presents a novel and comprehensive lipidomic profile of DLB, distinguishing it from AD and HCs. Predominantly, sphingolipids (e.g., ceramides and SPHs) and phospholipids (e.g., PE and PC) were the most dysregulated lipids in relation to DLB patients. The lipidomics panels identified through machine learning may serve as effective plasma biomarkers for diagnosing DLB and differentiating it from AD dementia.

Longitudinal lipidomic profiles of left ventricular mass and hypertrophy in American Indians.

Left ventricular hypertrophy (LVH) and dyslipidemia are strong, independent predictors for cardiovascular disease, but their relationship is less well-studied. A longitudinal lipidomic profiling of left ventricular mass (LVM) and LVH is still lacking. Using LC-MS, we repeatedly measured 1,542 lipids from 1,755 unique American Indians attending two exams (mean~5-year apart). Cross-sectional associations of individual lipid species with LVM index (LVMI) were examined by generalized estimating equation (GEE), followed by replication in an independent bi-racial cohort (65% white, 35% black). Baseline plasma lipids associated with LVH risk beyond traditional risk factors were identified by Cox frailty model in American Indians. Longitudinal associations between changes in lipids and changes in LVMI were examined by GEE, adjusting for baseline lipids, baseline LVMI, and covariates. Multiple lipid species (e.g., glycerophospholipids, sphingomyelins, acylcarnitines) were significantly associated with LVMI or the risk of LVH in American Indians. Some lipids were confirmed in black and white individuals. Moreover, some LVH-related lipids were inversely associated with risk of coronary heart disease (CHD). Longitudinal changes in several lipid species (e.g., glycerophospholipids, sphingomyelins, cholesterol esters) were significantly associated with changes in LVMI. These findings provide insights into the role of lipid metabolism in LV remodeling and the risk of LVH or CHD.

Serum lipidome reveals lipid metabolic dysregulation in severe fever with thrombocytopenia syndrome

BackgroundSevere fever with thrombocytopenia syndrome (SFTS) is a rapidly progressing infectious disease with a high fatality rate caused by a novel bunyavirus (SFTSV). The role of lipids in viral infections is well-documented; however, the specific alterations in lipid metabolism during SFTSV infection remain elusive. This study aims to elucidate the lipid metabolic dysregulations in the early stages of SFTS patients.MethodsThis study prospectively collected peripheral blood sera from 11 critical SFTS patients, 37 mild SFTS patients, and 23 healthy controls during the early stages of infection for lipidomics analysis. A systematic bioinformatics analysis was conducted from three aspects integrating lipid differential expressions, lipid differential correlations, and lipid-clinical indices correlations to reveal the serum lipid metabolic dysregulation in SFTSV-infected individuals.ResultsOur findings reveal significant lipid metabolic dysregulation in SFTS patients. Specifically, compared to healthy controls, SFTS patients exhibited three distinct modes of lipid differential expression: increased levels of lipids including phosphatidylserine (PS), hexosylceramide (HexCer), and triglycerides (TG); decreased levels of lipids including lysophosphatidylcholine (LPC), acylcarnitine (AcCa), and cholesterol esters (ChE); and lipids showing “dual changes” including phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Finally, based on lipid metabolic pathways and literature analysis, we systematically elucidated the potential mechanisms underlying lipid metabolic dysregulation in the early stage of SFTSV infection.ConclusionsOur study presents the first global serum lipidome profile and reveals the lipid metabolic dysregulation patterns in the early stage of SFTSV infection. These findings provide a new basis for the diagnosis, treatment, and further investigation of the disease.

Blood plasma lipid profile in glial tumors

Introduction. In glial tumors, lipid metabolism becomes abnormal. Analysis of lipid metabolism components can be an important characteristic of molecular and genetic profile of gliomas.Aim. To determine the correlation between plasma lipidome profile and immunohistochemical characteristics of glial tumors and to evaluate clinical significance of blood lipid spectrum analysis in preoperative assessment of molecular profile of gliomas.Materials and methods. Immunohistochemical measurement of O-6-methylguanine-DNA-methyl transferase (MGMT), Ki-67, p53, IDH1 tumor markers was performed using the corresponding antibody clones. Composition of plasma lipids was assessed using thin layer chromatography.Results. Even at the early stages of gliomagenesis, significant differences in cholesterol ethers, lysophosphatidylcholines, phosphatidylcholine (PC)/ lysophosphatidylcholine (LPC) ratio, neutral lipids (NL)/phospholipids (PL) in the blood were observed. Significant correlations between Ki-67, MGMT tumor markers and the above-mentioned lipidome parameters were found. The PC/LPC, NL/PL ratios in the blood of the patients from the groups with higher (above 10 %) and lower (below 10 %) Ki-67 mitotic indexes compared to healthy individuals were significantly lower. Therefore, the values of lipidome parameters allow to indirectly assess proliferative activity of gliomas which can be used for preoperative diagnosis of these tumors. No significant differences in the plasma PC/LPC and NL/PL ratios were found between the groups with MGMT promoter methylation and without it. No indirect predictor criteria for MGMT were found.Conclusion. It is impossible to determine decreased epigenetic activity of corresponding transcripts and preoperative prognosis for alkylating agent therapy based on the parameters of plasma lipid metabolism.

Exposure to PFOA, PFOS, and PFHxS induces Alzheimer's disease-like neuropathology in cerebral organoids

Per- and polyfluoroalkyl substances (PFASs), a class of ubiquitous synthetic organic chemicals, are widely utilized across various industrial applications. However, the long-term neurological health effects of PFAS mixture exposure in humans remain poorly understood. To address this gap, we have designed a comprehensive study to predict and validate cell-type-specific neurotoxicity of PFASs using single-cell RNA sequencing (scRNA-seq) and cerebral organoids. Cerebral organoids were exposed to a PFAS mixture at concentrations of 1 × (10 ng/ml PFOS and PFOA, and 1 ng/ml PFHxS), 30 × , and 900 × over 35 days, with a follow-up analysis at day 70. Pathological alterations and lipidomic profiles were analyzed to identify disrupted molecular pathways and mechanisms. The scRNA-seq data revealed a significant impact of PFASs on neurons, suggesting a potential role in Alzheimer's Disease (AD) pathology, as well as intellectual and cognitive impairments. PFAS-treated cerebral organoids exhibited Aβ accumulation and tau phosphorylation. Lipidomic analyses further revealed lipid disturbances in response to PFAS mixture exposure, linking PFAS-induced AD-like neuropathology to sphingolipid metabolism disruption. Collectively, our findings provide novel insights into the PFAS-induced neurotoxicity, highlighting the significance of sphingolipid metabolism in the development of AD-like neuropathology. The use of cerebral organoids and scRNA-seq offers a powerful methodology for evaluating the health risks associated with environmental contaminants, particularly those with neurotoxic potential.

Exploring the circulating metabolome of sepsis: metabolomic and lipidomic profiles sampled in the ambulance

BackgroundSepsis is defined as a dysfunctional host response to infection. The diverse clinical presentations of sepsis pose diagnostic challenges and there is a demand for enhanced diagnostic markers for sepsis as well as an understanding of the underlying pathological mechanisms involved in sepsis. From this perspective, metabolomics has emerged as a potentially valuable tool for aiding in the early identification of sepsis that could highlight key metabolic pathways and underlying pathological mechanisms.ObjectiveThe aim of this investigation is to explore the early metabolomic and lipidomic profiles in a prospective cohort where plasma samples (n = 138) were obtained during ambulance transport among patients with infection according to clinical judgement who subsequently developed sepsis, patients who developed non-septic infection, and symptomatic controls without an infection.MethodsMultiplatform metabolomics and lipidomics were performed using UHPLC–MS/MS and UHPLC–QTOFMS. Uni- and multivariable analysis were used to identify metabolite profiles in sepsis vs symptomatic control and sepsis vs non-septic infection.ResultsUnivariable analysis disclosed that out of the 457 annotated metabolites measured across three different platforms, 23 polar, 27 semipolar metabolites and 133 molecular lipids exhibited significant differences between patients who developed sepsis and symptomatic controls following correction for multiple testing. Furthermore, 84 metabolites remained significantly different between sepsis and symptomatic controls following adjustment for age, sex, and Charlson comorbidity score. Notably, no significant differences were identified in metabolites levels when comparing patients with sepsis and non-septic infection in univariable and multivariable analyses.ConclusionOverall, we found that the metabolome, including the lipidome, was decreased in patients experiencing infection and sepsis, with no significant differences between the two conditions. This finding indicates that the observed metabolic profiles are shared between both infection and sepsis, rather than being exclusive to sepsis alone.

8182 New Mouse Model Mirrors Human MODY8: Opening Doors to Understanding Exocrine-Endocrine Crosstalk in the Diabetic Pancreas

Abstract Disclosure: K. El Jellas: None. V. Salerno: None. L.S. Katz: None. J. Hu: None. G. Fogarty: None. A. Mandal: None. A. DiStefano-Forti: None. D. Scott: None. M. Lowe: None. A. Molven: None. R.N. Kulkarni: None. Maturity-onset diabetes of the young, type 8 (MODY8) is a dominantly inherited form of monogenic diabetes, caused by heterozygous mutations in the carboxyl ester lipase (CEL) gene expressed in pancreatic acinar cells. MODY8 is characterized by chronic pancreatitis and exocrine dysfunction. Despite the intimate anatomical relationship between the endocrine and exocrine pancreas, little is known about the biological components mediating exocrine-endocrine communication in regulating glucose homeostasis. Here, we report a refined mouse model that bears the mutation present in MODY8 patients on one allele, and the humanized normal variable number of tandem repeat (VNTR) of CEL with 16 repeats (16R) on the other, mimicking the genetic make-up seen in MODY8 patients. Examination of glucose homeostasis revealed that inducing stress (e.g. by high-fat diet) leads to glucose intolerance in MODY8/16R mice and a blunted glucose-stimulated insulin-secretion compared to their control littermates. Histopathological analyses demonstrated features of chronic pancreatitis in some pancreatic lobes, including inflammation, acinar atrophy, acinar-to-ductal metaplasia, fibrosis and fat infiltration, mirroring the morphology of the human disease. Moreover, we applied immunolabeling-enabled three-dimensional imaging of solvent-cleared organs (iDISCO) to intact pancreata and found that beta-cell mass was significantly decreased in the MODY8/16R mice, with a large number of islets located within fatty lobes. These results are coupled with comparative proteomics and lipidomic profiling with the aim of understanding the molecular signatures of exocrine and endocrine cells during pathogenesis. In conclusion, we have generated a mouse that recapitulates several features of the exocrine and endocrine phenotype characteristic of human MODY8. This novel model provides a unique opportunity, not possible in humans, to characterize pancreatic endocrine-exocrine communication in a longitudinal manner as a response to diverse environmental stressors. Presentation: 6/2/2024

Systemic messenger RNA replacement therapy is effective in a novel clinically relevant model of acute intermittent porphyria developed in non-human primates

ObjectiveAcute intermittent porphyria (AIP) is a rare metabolic disorder caused by haploinsufficiency of hepatic porphobilinogen deaminase (PBGD), the third enzyme of the heme biosynthesis. Individuals with AIP experience neurovisceral attacks...

Recommendations for Accurate Lipid Annotation and Semi-absolute Quantification from LC-MS/MS Datasets.

Recent developments in LC-MS instrumentation and analytical technologies together with bioinformatics tools supporting high-throughput processing of large omics datasets significantly enhanced our capabilities and efficiency of identification and quantification of lipids in diverse biological materials. However, each biological matrix is characterized by its unique lipid composition, thus requiring optimization of analytical and bioinformatics workflows for each studied lipidome. Here, we describe an integrated workflow for deep lipidome profiling, accurate annotation, and semi-absolute quantification of complex lipidomes based on reversed phase chromatography and high resolution mass spectrometry. This chapter provides details on selection of the optimal extraction protocol, acquisition of LC-MS/MS data for accurate annotation of lipid molecular species, and design of lipidome-specific mixtures of internal standards to assist quantitative analysis of complex, native lipidomes.

Effects Of Different Doses Of Supervised Physical Exercise On The Lipidomic Profile Among Adolescents With Overweight/obesity: The Hepafit Study

Effects Of Different Doses Of Supervised Physical Exercise On The Lipidomic Profile Among Adolescents With Overweight/obesity: The Hepafit Study

In-depth cerebrovascular lipidomics profiling for discovering novel biomarkers and mechanisms in moyamoya and intracranial atherosclerotic disease.

Despite considerable research efforts, the precise etiology and underlying pathways contributing to Moyamoya Disease (MMD) remain poorly understood. Moreover, the overlapping vascular pathologies shared between MMD and Intracranial Atherosclerotic Disease (ICAD) pose challenges in clinical differentiation, even with gold-standard cerebral angiography. An in-depth exploration of lipidomic alterations in cerebral intracranial MMD vessels could offer valuable insights into the pathogenesis of MMD-related mechanisms, encompassing MMD and ICAD, and unveil novel biomarkers and potential therapeutic targets. However, to date, comprehensive lipidomic profiling has been lacking. To discover novel biomarkers and unravel the pathophysiological mechanisms underlying MMD, we conducted a lipidomics analysis to characterize various lipid species in matched human extracranial and intracranial artery tissues from patients diagnosed with MMD (n=99) and ICAD (n=12). Our analysis identified 569 lipid species and delineated a robust panel of lipidomic biomarkers capable of effectively distinguishing MMD from ICAD (area under curve=0.98), as determined by receiver operating characteristic curve analysis. Notably, we observed a significantly more pronounced positive correlation of diacylglycerols and a negative association of triglycerides in intracranial artery tissues of MMD patients compared to those with ICAD, suggesting a potential role of dysregulated diacylglycerol-induced signaling in MMD pathogenesis. Furthermore, our investigation into the correlations of critical differential intracranial artery vessel lipid species between MMD and ICAD and clinical parameters revealed negative associations with plasma iron levels, implying a potential link between plasma iron metabolism and artery lipid homeostasis during MMD pathogenesis. These findings offer promising prospects for advancing clinical diagnosis for enhanced differentiation between the two disease conditions. Additionally, they shed light on the fundamental mechanisms implicated in MMD pathogenesis and suggest potential therapeutic avenues through targeting artery vessel lipids or plasma iron levels.

Highly reliable LC-MS lipidomics database for efficient human plasma profiling based on NIST SRM 1950

Liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS)-based methods have become the gold standard methodology for the comprehensive profiling of the human plasma lipidome. However, both the complexity of lipid chemistry and LC-HRMS-associated data pose challenges to the characterization of this biological matrix. In accordance with the current consensus of quality requirements for LC-HRMS lipidomics data, we aimed to characterize the NIST® Standard Reference Material for Human Plasma (SRM 1950) using an LC-ESI(+/–)-MS method compatible with high-throughput lipidome profiling. We generated a highly curated lipid database with increased coverage, quality, and consistency, including additional quality assurance procedures involving adduct formation, within-method m/z evaluation, retention behavior of species within lipid chain isomers, and expert-driven resolution of isomeric and isobaric interferences. As a proof-of-concept, we showed the utility of our in-house LC-MS lipidomic database –consisting of 592 lipid entries– for the fast, comprehensive, and reliable lipidomic profiling of the human plasma from healthy human volunteers. We are confident that the implementation of this robust resource and methodology will have a significant impact by reducing data redundancy and the current delays and bottlenecks in untargeted plasma lipidomic studies.