Sphingolipid metabolism and signaling in cardiovascular diseases

Exploring the cardiotoxic potential of fumonisin B1 through inflammatory pathways and epigenetic modifications: A mini review

This review is centered around the cardiotoxic effects of fumonisin B1 (FB1), particularly its impact on sphingolipid metabolism, inflammation, and epigenetics. FB1 is a mycotoxin produced by Fusarium fungi, which mainly contaminates cereal grains and poses an adverse health risk to both humans and animals; however, its disease-causing capabilities remain to be uncovered, specifically its ability to exacerbate and cause cardiovascular disease. It disrupts sphingolipid metabolism by inhibiting ceramide synthase, leading to cellular dysfunction and contributes to conditions such as hypertension and eventual heart failure. FB1 is responsible for an altered inflammatory response, whereby it increases pro-inflammatory cytokines such as IL-6 and IL-1β, which contribute to cardiovascular diseases. Moreover, FB1 induces significant epigenetic changes, including DNA hypermethylation, histone modifications such as increased H3K9me2 and H3K9me3, inhibition of histone acetyltransferase activity, and changes in microRNA expression profiles. These epigenetic alterations can silence or activate inflammatory genes, exacerbating disease progression. This review thus highlights the need for further research to elucidate the connections between FB1, inflammation, epigenetic modifications, and cardiotoxicity, which could lead to better strategies for managing FB1-related adverse health risks.

Tongfu Xingshen capsule alleviates stroke-associated pneumonia-induced multiple organ injuries by modulating the gut microbiota and sphingolipid metabolism

BACKGROUND

Stroke-associated pneumonia (SAP) represents a major complication and cause of death in patients suffering from intracerebral haemorrhage (ICH). It's urgent to develop more effective therapeutic strategies. Tongfu Xingshen capsule (TFXS) is a traditional Chinese medicine that has been utilised in clinical studies for the treatment of ICH and SAP, but the underlying mechanisms remain to be fully elucidated.

PURPOSE

This study aims to explore the therapeutic effects and mechanisms of TFXS on SAP using an aspiration-induced Klebsiella pneumoniae infection-complicating ICH rat model and an intratracheal injection of lipopolysaccharide (LPS)-induced acute lung injury-complicating ICH rat model.

METHODS

The chemical components of TFXS are characterised using ULPLC-Q Exactive-Orbitrap-MS. The therapeutic effects of TFXS are evaluated through neurological scoring, histopathology analysis, magnetic resonance imaging, immunofluorescence, Alcian blue-nuclear fast red staining, myeloperoxidase activity assessment, leukocyte counting, and ELISA. To investigate the underlying mechanisms, faecal microbiota transplantation, 16S rRNA sequencing, untargeted metabolomics, and Spearman correlation analyses are performed.

RESULTS

A total of 60 compounds are identified in TFXS. Pharmacological analysis reveals that TFXS significantly mitigates neurological deficits, enhances haematoma absorption, attenuates brain damage and neuroinflammation, and improves pneumonia and pulmonary injury by reducing the infiltration of leukocytes and lymphocytes, as well as suppressing the infiltration and overactivation of neutrophils. TFXS also alleviates intestinal lesions and barrier damage by increasing acidic mucins and the expression of the tight junction protein zonula occludens-1 (ZO-1). Mechanistically, TFXS ameliorates pneumonia and pulmonary injury in a gut microbiota-dependent manner. It reverses sphingolipid metabolism disorders and ceramide accumulation by modulating SAP-induced gut microbiota dysbiosis and enhancing the abundance of probiotics, including Lactobacillus, Allobaculum and Enterococcus.

CONCLUSION

TFXS exerts anti-inflammatory and protective effects on the brain, lung, and gut by alleviating gut microbiota dysbiosis and sphingolipid metabolism disorders. These findings highlight TFXS as a promising therapeutic candidate for the treatment of SAP.

A narrative review of metabolomics approaches in identifying biomarkers of doxorubicin-induced cardiotoxicity

BACKGROUND

While anthracyclines, commonly used in cancer treatment, are well known to cause cardiotoxicity, no validated biomarkers currently exist that can predict the early development of doxorubicin-induced cardiotoxicity (DIC). Therefore, identifying early biomarkers of DIC is urgently needed. Metabolomics approaches have been used to elucidate this relationship and identified related metabolite markers. However, differences in pre-clinical model systems make it challenging to draw definitive conclusions from the discoveries and translate findings into clinical applications.

AIM OF REVIEW

A systematic literature search on metabolomics studies of DIC was conducted with the goal to identify and compare study results reported using in vitro models, animal models, and studies from clinical patients. Metabolites identified across all studies were pooled to uncover biologically meaningful patterns that are significantly enriched in the data. Finally, pooled metabolites perturbed by DIC were mapped to metabolic pathways to explore potential pathological implications.

RESULTS

We reviewed 28 studies published between 2000 and 2024 that utilized metabolomics approaches to investigate DIC. The included studies used a variety of analytical techniques, including LC-MS, GC-MS, and NMR. The analysis revealed that metabolites such as inosine, phenylalanine, arginine, and tryptophan were commonly perturbed across all study models, with carnitine metabolism and purine and pyrimidine metabolism being the most affected pathways. Metabolite Set Enrichment Analysis (MSEA) using MetaboAnalyst identified the arginine biosynthesis, citrate cycle, and alanine, aspartate, and glutamate metabolism pathways as significantly enriched.

CONCLUSION

These findings underscore the potential of metabolomics in identifying early biomarkers for DIC, providing a foundation for future studies aimed at preventing cardiotoxicity and improving treatment strategies for cancer patients receiving DOX-containing therapies.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Altogether, metabolomics studies suggest metabolic alterations in DIC, albeit little overlap between studies especially with animal and human studies. Attempts at intercepting these pathways have shown that intervention in DIC may be possible. Future research should focus on developing precise cardiotoxicity models that incorporate cancer metabolism, as these will be crucial in bridging the gap between laboratories (in vitro and animal models) and clinical studies to identify subclinical biomarkers in the early stage of DIC that can effectively identify new targets for interventions to reduce lethal cardiovascular disease risk.

Coronary artery disease is associated with particular change of serum metabolome: a case-control study

INTRODUCTION

Cardiovascular disease (CVD) is a significant cause of mortality worldwide. Preventive programs are trying to reduce the burden of the disease. Recent advances in metabolomics profiling open a new avenue for developing complementary CVD evaluation strategies.

OBJECTIVES

The aim of the study was to investigate whether a metabolomic profile can provide an additional characterisation of individuals with coronary artery disease (CAD).

METHODS

The study included 167 participants with CAD aged 41-79 years. A control group was formed of 166 individuals without CAD, gender- and age-matched to the study group. A total of 188 metabolites were profiled in serum by liquid chromatography-tandem mass spectrometry. After clearing the data, associations between 132 metabolites and CAD presence were analysed using multiple linear regression models.

RESULTS

We observed significant differences in serum metabolic profiles between analysed groups on various levels. However, a deeper analysis revealed sphingomyelin 41:1 (SM 41:1) as the main metabolite independently associated with CAD after correction for classical CV risk factors. Its concentration was lower in the CAD group (median 9.79 µmol/L, interquartile range (IQR) 7.92-12.23) compared to control one (median 13.60 µmol/L, IQR 11.30-16.15) (p < 0.001). Further analysis showed that SM 41:1 concentration was inversely correlated with CAD, current smoking, and hypertension; and positively associated with female gender and non-HDL level.

CONCLUSIONS

CAD patients present lower plasma concentrations of SM 41:1 than healthy subjects. A better understanding of the biological function of sphingomyelin in CAD patients may help develop therapeutic approaches and risk stratification in this group.

Identification of Hub Genes for Dexmedetomidine Alleviation of Limb Ischemia-Reperfusion-Induced Lung Injury in Rats by Transcriptomic

Background

Limb ischemia-reperfusion (LIR), a prevalent clinical condition, frequently precipitates acute lung injury (ALI). Dexmedetomidine (DEX), a selective alpha2-adrenergic receptor agonist, mitigates LIR-induced ALI. However, its underlying mechanisms remain incompletely elucidated. This study aimed to identify hub genes implicated in DEX-mediated protection against LIR-ALI in rats.

Methods

Sprague-Dawley rats were allocated into five groups (n = 3 per group): Sham (femoral artery exposure without occlusion), LIR, LIR + DEX, LIR + Inhibitor, and LIR + DEX + Inhibitor. LIR was induced by clamping the femoral arteries for 3 hours, followed by reperfusion. DEX (50 μg/kg) or Atipamezole (alpha2-receptor inhibitor, 250 μg/kg) was administered prior to ischemia. Lung injury was evaluated via hematoxylin-eosin staining, wet/dry ratio assessment, and quantification of IL-1beta, TNF-alpha, malondialdehyde (MDA), and superoxide dismutase (SOD) levels. RNA sequencing was performed to identify differentially expressed genes (DEGs), followed by functional enrichment analysis, protein-protein interaction (PPI) network construction, and hub gene identification. Gene-gene interaction (GGI) networks were established. Polymerase chain reaction (PCR) and enzyme linked immunosorbent assay (ELISA) validation was conducted.

Results

LIR induced severe lung injury and inflammation, both of which were attenuated by DEX pretreatment. RNA sequencing identified 2,302 DEGs1, 471 DEGs2, 340 DEGs3, and 1,407 DEGs4. After intersection and subtraction analyses, 255 DEX-associated DEGs (DEGs-Dex) and 290 inhibitor-associated DEGs (DEGs-In) were identified, with enrichment in Wnt/PI3K-Akt signaling (DEX) and glycerolipid/butanoate metabolism (In). Nine Hub-Dex genes and four Hub-In genes were identified, among which Selp and Tars1 exhibited a strong positive correlation (correlation = 0.55, P < 0.05). Six hub genes (Tars1, Atf4, Ep300, Sphk1, AABR07051376.1, and Mmp9) were validated.

Conclusion

Six hub genes associated with DEX-mediated protection against LIR-ALI were identified, providing mechanistic insights and potential therapeutic targets for intervention.

Sphingolipid Metabolism and Signalling Pathways in Heart Failure: From Molecular Mechanism to Therapeutic Potential

Sphingolipids are essential components of cell membranes and lipoproteins. They are synthesized de novo in the endoplasmic reticulum and subsequently undergo various enzymatic modifications in different organelles, giving rise to a diverse range of biologically active compounds. These molecules play a critical role in regulating cell growth, senescence, migration, apoptosis, and signaling. In recent years, the sphingolipid metabolic pathway has been recognized as a key factor in heart failure (HF) pathophysiology. Abnormal levels of sphingolipid metabolites, such as ceramide (Cer) and sphingomyelin (SM), contribute to oxidative stress and inflammatory responses, ultimately promoting cardiomyocyte apoptosis. Conversely, sphingosine-1-phosphate (S1P) and ceramide-1-phosphate (C1P) regulate vascular function and influence cardiac remodeling. Additionally, enzymes such as diacylglycerol acyltransferase 1 (DGAT1) and sphingosine-1-phosphate lyase 1 (SGPL1) modulate cardiac lipid metabolism. Given their role in HF progression, monitoring sphingolipid alterations offers potential as valuable biomarkers for assessing disease severity, prognosis, and diagnosis. Given the complexity of sphingolipid metabolism and its involvement in diverse regulatory biological processes, a comprehensive understanding of its roles at both the cellular and organismal levels in physiopathology remains incomplete. Therefore, this review aims to explore the physiological functions, regulatory mechanisms, and therapeutic potential of sphingolipid metabolism. It will summarize the specific molecular mechanisms driving key pathological processes in HF, including ventricular remodeling, myocardial fibrosis, vascular dysfunction, and metabolic disorders. Finally, the review will highlight targeted sphingolipid metabolites as potential therapeutic strategies, offering new insights into HF diagnosis and treatment, with the goal of advancing adjunctive clinical therapies.

Association of PM2.5-bound multiple metals co-exposure with early cardiovascular damage: A panel study in young adults combining metabolomics

The association of individual metals in PM2.5 with cardiovascular damage has been established in previous studies, but there are fewer studies on co-exposure to multiple metals and potential metabolic alterations in cardiovascular damage. To investigate the early cardiovascular effects of multiple metals and the mediating effects of metabolites, we conducted a panel study on young adults from 2017 Winter to 2018 Autumn in Caofeidian, China. A total of 180 serum samples were analyzed for metabolomic profiles using liquid chromatography-mass spectrometry. The associations between personal metal exposure, metabolite levels, and indicators of cardiovascular injury were analyzed by linear mixed-effects modeling (LME) and Bayesian kernel machine regression (BKMR). Metabolomic analyses showed 79 metabolites in the serum of healthy adults changed significantly between seasons and all metabolites were strongly associated with toxic metals. Additionally, differential metabolites were enriched in seven metabolic pathways and activated by metal exposure, such as Butanoate metabolism and Linoleic acid metabolism. BKMR model interpreted that the overall effect of metals mixture was negatively associated with Capryloyl glycine and Sphinganine and Sb mainly contributed to the effect. The results of mediation analysis revealed that the association between V and VEGF was mediated by Diethylhexyl with a partial proportion of 13.4%. Furthermore, the result also found the association between CerP(d18:1/26:1(17Z)) and ET-1 was mediated by TGFβ1 with a proportion of 53.4%. Our findings suggested that multiple metal exposure was associated with metabolomic changes of cardiovascular damage in young adults, and may simultaneously affect the metabolomic changes by inducing oxidative stress and inflammation.

Triglyceride-rich lipoprotein sphingolipids are altered in primary hypertension: A pilot case-control study

BACKGROUND

Sphingolipids modulate vascular function and alterations in plasma sphingolipid profiles have been associated with hypertension. Plasma sphingolipids, such as ceramides (Cer) and sphingosine-1-phosphate (S1P), are predominantly carried by lipoproteins.

OBJECTIVE

We compared sphingolipid profiles in plasma and isolated lipoproteins of patients with primary hypertension with those of normotensive controls.

METHODS

Blood was obtained from 19 patients with hypertension and 19 age- and sex-matched normotensive controls. S1P and the 7 most abundant Cer were quantified by liquid chromatography-tandem mass spectrometry in plasma and in lipoproteins.

RESULTS

Total plasma Cer were significantly higher in patients with hypertension compared to controls (14.3 ± 1.0 vs 11.9 ± 0.7 µM; P = .047), while there were no differences in plasma S1P levels (1.8 ± 0.1 vs 2.1 ± 0.1 µM; P = .128). Total Cer carried by patient triglyceride-rich lipoproteins (TRL; ie, predominantly very low-density lipoproteins) were also significantly higher (1.33 ± 0.15 vs 0.58 ± 0.10 µM; P = .001), which held for all Cer tested. Systolic blood pressure positively correlated with plasma levels of Cer(d18:1/20:0) and Cer(d18:1/24:1), and diastolic blood pressure positively correlated with total Cer, Cer(d18:1/18:0), Cer(d18:1/20:0) and Cer(d18:1/24:0). Relative to plasma Cer(d18:1/24:0), levels of Cer(d18:1/18:0), Cer(d18:1/20:0) and Cer(d18:1/24:1) were significantly higher in patients with hypertension than in controls.

CONCLUSION

Patients with hypertension display higher plasma Cer levels than normotensive controls, which is mainly explained by elevated concentrations in TRLs. Cer levels positively correlate with systolic and diastolic blood pressure, and ratios of Cer relative to Cer(d18:1/24:0) suggest an increased cardiovascular risk.

Rat models of postintracerebral hemorrhage pneumonia induced by nasal inoculation with Klebsiella pneumoniae or intratracheal inoculation with LPS

Background

A stable and reproducible experimental bacterial pneumonia model postintracerebral hemorrhage (ICH) is necessary to help investigating the pathogenesis and novel treatments of Stroke-associated pneumonia (SAP).

Aim

To establish a Gram-negative bacterial pneumonia-complicating ICH rat model and an acute lung injury (ALI)-complicating ICH rat model.

Methods

We established two standardized models of post-ICH pneumonia by nasal inoculation with Klebsiella pneumoniae (Kp) or intratracheal inoculation with lipopolysaccharide (LPS). Survival and neurological scores were monitored. Magnetic resonance imaging was performed to evaluate hematoma volume. Abdominal aortic blood was collected for leukocyte counting, serum was isolated to determine concentrations of S100β and proinflammatory cytokines using ELISAs. Histopathological changes of brain, lung and gut were assessed using hematoxylin-eosin staining. Lung was isolated for immunofluorescence staining for myeloperoxidase (MPO). Bronchoalveolar lavage fluid was collected for leukocyte counting, and supernatant was prepared to measure MPO activity. Ileum was isolated for immunofluorescence staining for tight junction proteins ZO-1 and γδ TCRs/IL-17A and for Alcian blue-nuclear fast red staining of acidic mucins. Feces were collected, 16S rRNA sequencing, untargeted metabolomics and Spearman's correlation analyses were performed to explore changes of gut microbiota, metabolites and their interactions.

Results

In Kp-induced bacterial pneumonia-complicating ICH rats, we demonstrated that Kp challenge caused more severe neurological deficits, brain damage, neuroinflammation, and aggravated pneumonia and lung injury. Disruptions of the intestinal structure and gut barrier and the reductions of the protective intestinal IL-17A-producing γδT cells were also observed. Kp challenge exacerbated the gut microbiota dysbiosis and fecal metabolic profile disorders, which were characterized by abnormal sphingolipid metabolism especially elevated ceramide levels; increased levels of neurotoxic quinolinic acid and an upregulation of tryptophan (Trp)-serotonin-melatonin pathway. Spearman's correlation analyses further revealed that the reduction or depletion of some beneficial bacteria, such as Allobaculum and Faecalitalea, and the blooming of some opportunistic pathogens, such as Turicibacter, Dietzia, Corynebacterium and Clostridium_sensu_stricto_1 in Kp-induced SAP rats were associated with the disordered sphingolipid and Trp metabolism. Using an LPS-induced ALI complicating ICH model, we also characterized SAP-induced brain, lung and gut histopathology injuries; peripheral immune disorders and intense pulmonary inflammatory responses.

Conclusions

These two models may be highly useful for investigating the pathogenesis and screening and optimizing potential treatments for SAP. Moreover, the differential genera and sphingolipid or Trp metabolites identified above seem to be promising therapeutic targets.

Cardioprotective microRNAs (protectomiRs) in a pig model of acute myocardial infarction and cardioprotection by ischaemic conditioning: MiR-450a

BACKGROUND AND PURPOSE

Cardioprotective miRNAs (protectomiRs) are promising therapeutic tools. Here, we aimed to identify protectomiRs in a translational porcine model of acute myocardial infarction (AMI) and to validate their cardiocytoprotective effect.

EXPERIMENTAL APPROACH

ProtectomiR candidates were selected after systematic analysis of miRNA expression changes in cardiac tissue samples from a closed-chest AMI model in pigs subjected to sham operation, AMI and ischaemic preconditioning, postconditioning or remote preconditioning, respectively. Cross-species orthologue protectomiR candidates were validated in simulated ischaemia-reperfusion injury (sI/R) model of isolated rat ocardiomyocytes and in human AC16 cells as well. For miR-450a, we performed target prediction and analysed the potential mechanisms of action by GO enrichment and KEGG pathway analysis.

KEY RESULTS

Out of the 220 detected miRNAs, four were up-regulated and 10 were down-regulated due to all three conditionings versus AMI. MiR-450a and miR-451 mimics at 25 nM were protective in rat cardiomyocytes, and miR-450a showed protection in human cardiomyocytes as well. MiR-450a has 3987 predicted mRNA targets in pigs, 4279 in rats and 8328 in humans. Of these, 607 genes are expressed in all three species. A total of 421 common enriched GO terms were identified in all three species, whereas KEGG pathway analysis revealed 13 common pathways.

CONCLUSION AND IMPLICATIONS

This is the first demonstration that miR-450a is associated with cardioprotection by ischaemic conditioning in a clinically relevant porcine model and shows cardiocytoprotective effect in human cardiomyocytes, making it a promising drug candidate. The mechanism of action of miR-450a involves multiple cardioprotective pathways.

LINKED ARTICLES

This article is part of a themed issue Non-coding RNA Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.2/issuetoc.

Glycosphingolipids in Cardiovascular Disease: Insights from Molecular Mechanisms and Heart Failure Models

This review explores the crucial role of glycosphingolipids (GSLs) in the context of cardiovascular diseases (CVDs), focusing on their biosynthesis, metabolic pathways, and implications for clinical outcomes. GSLs are pivotal in regulating a myriad of cellular functions that are essential for heart health and disease progression. Highlighting findings from both human cohorts and animal models, this review emphasizes the potential of GSLs as biomarkers and therapeutic targets. We advocate for more detailed mechanistic studies to deepen our understanding of GSL functions in cardiovascular health, which could lead to innovative strategies for diagnosis, treatment, and personalized medicine in cardiovascular care.

The Combination of Gastrodin and Gallic Acid Synergistically Attenuates AngII-Induced Apoptosis and Inflammation via Regulation of Sphingolipid Metabolism

Background

Hypertension (HTN) is closely related to endothelial damage. While tianma (TM) and gouqizi (GQZ) have the potential to be effective in the treatment of HTN in traditional Chinese medicine, their main active ingredients and whether its exert synergistic effects and the underlying mechanisms of synergistic effects are still unclear.

Objective

This study screened the active ingredients of TM and GQZ, investigated the synergistic effects of the active ingredients and explored possible mechanisms.

Methods

The potential targets and mechanisms of TM and GQZ were screened using network pharmacology, and gastrodin (GAS) and gallic acid (GA) were identified as compounds with significant antihypertensive activity. The synergistic effects of the combination of GAS and GA was assessed by measuring biomarkers of AngII-induced human umbilical vein endothelial cell (HUVECs) dysfunction model. Furthermore, the anti-apoptotic and anti-inflammatory effects were evaluated by measuring inflammatory cytokine secretion, and apoptosis-related markers. Finally, key targets of the sphingolipid signaling pathway were experimentally validated by Western blotting.

Results

In network pharmacology, the herb-pair exerted a synergetic effect by regulating sphingolipid pathways. The GAS and GA exerted synergistic protective effects in AngII-induced HUVECs injury by improving Nitric Oxide Content (NO) levels, alleviating lactate Endothelin-1 (ET-1), and Thromboxane B2 (TX-B2) release, reducing the secretion of inflammatory factors like interleukin-6 (IL-6), interleukin-1β (IL-1β), Tumor Necrosis Factor Alpha (TNF-α)), decreasing the pro-apoptotic protein BAX, and increasing the anti-apoptotic protein BCL-2. Furthermore, the results showed that the GAS and GA combination could elevate the level of S1PR1 and inhibit the expression of ROCK2 and the phosphorylation of NF-κB, which are key targets involved in sphingolipid pathways.

Conclusion

Our study revealed that the combination of GAS and GA could suppress inflammation and apoptosis, which are highly correlated with sphingolipid signaling pathways, making it a potential candidate for the treatment of HTN.

Emerging Roles for Sphingolipids in Cardiometabolic Disease: A Rational Therapeutic Target?

Cardiovascular disease is a leading cause of morbidity and mortality. New research elucidates increasingly complex relationships between cardiac and metabolic health, giving rise to new possible therapeutic targets. Sphingolipids are a heterogeneous class of bioactive lipids with critical roles in normal human physiology. They have also been shown to play both protective and deleterious roles in the pathogenesis of cardiovascular disease. Ceramides are implicated in dysregulating insulin signalling, vascular endothelial function, inflammation, oxidative stress, and lipoprotein aggregation, thereby promoting atherosclerosis and vascular disease. Ceramides also advance myocardial disease by enhancing pathological cardiac remodelling and cardiomyocyte death. Glucosylceramides similarly contribute to insulin resistance and vascular inflammation, thus playing a role in atherogenesis and cardiometabolic dysfunction. Sphingosing-1-phosphate, on the other hand, may ameliorate some of the pathological functions of ceramide by protecting endothelial barrier integrity and promoting cell survival. Sphingosine-1-phosphate is, however, implicated in the development of cardiac fibrosis. This review will explore the roles of sphingolipids in vascular, cardiac, and metabolic pathologies and will evaluate the therapeutic potential in targeting sphingolipids with the aim of prevention and reversal of cardiovascular disease in order to improve long-term cardiovascular outcomes.

Investigating Genetic Overlap between Alzheimer's Disease, Lipids, and Coronary Artery Disease: A Large-Scale Genome-Wide Cross Trait Analysis

There is evidence to support a link between abnormal lipid metabolism and Alzheimer's disease (AD) risk. Similarly, observational studies suggest a comorbid relationship between AD and coronary artery disease (CAD). However, the intricate biological mechanisms of AD are poorly understood, and its relationship with lipids and CAD traits remains unresolved. Conflicting evidence further underscores the ongoing investigation into this research area. Here, we systematically assess the cross-trait genetic overlap of AD with 13 representative lipids (from eight classes) and seven CAD traits, leveraging robust analytical methods, well-powered large-scale genetic data, and rigorous replication testing. Our main analysis demonstrates a significant positive global genetic correlation of AD with triglycerides and all seven CAD traits assessed-angina pectoris, cardiac dysrhythmias, coronary arteriosclerosis, ischemic heart disease, myocardial infarction, non-specific chest pain, and coronary artery disease. Gene-level analyses largely reinforce these findings and highlight the genetic overlap between AD and three additional lipids: high-density lipoproteins (HDLs), low-density lipoproteins (LDLs), and total cholesterol. Moreover, we identify genome-wide significant genes (Fisher's combined p value [FCPgene] < 2.60 × 10-6) shared across AD, several lipids, and CAD traits, including WDR12, BAG6, HLA-DRA, PHB, ZNF652, APOE, APOC4, PVRL2, and TOMM40. Mendelian randomisation analysis found no evidence of a significant causal relationship between AD, lipids, and CAD traits. However, local genetic correlation analysis identifies several local pleiotropic hotspots contributing to the relationship of AD with lipids and CAD traits across chromosomes 6, 8, 17, and 19. Completing a three-way analysis, we confirm a strong genetic correlation between lipids and CAD traits-HDL and sphingomyelin demonstrate negative correlations, while LDL, triglycerides, and total cholesterol show positive correlations. These findings support genetic overlap between AD, specific lipids, and CAD traits, implicating shared but non-causal genetic susceptibility. The identified shared genes and pleiotropic hotspots are valuable targets for further investigation into AD and, potentially, its comorbidity with CAD traits.

Angiotensin II Alters Mitochondrial Membrane Potential and Lipid Metabolism in Rat Colonic Epithelial Cells

An over-active renin-angiotensin system (RAS) is characterized by elevated angiotensin II (Ang II). While Ang II can promote metabolic and mitochondrial dysfunction in tissues, little is known about its role in the gastrointestinal system (GI). Here, we treated rat primary colonic epithelial cells with Ang II (1-5000 nM) to better define their role in the GI. We hypothesized that Ang II would negatively affect mitochondrial bioenergetics as these organelles express Ang II receptors. Ang II increased cellular ATP production but reduced the mitochondrial membrane potential (MMP) of colonocytes. However, cells maintained mitochondrial oxidative phosphorylation and glycolysis with treatment, reflecting metabolic compensation with impaired MMP. To determine whether lipid dysregulation was evident, untargeted lipidomics were conducted. A total of 1949 lipids were detected in colonocytes spanning 55 distinct (sub)classes. Ang II (1 nM) altered the abundance of some sphingosines [So(d16:1)], ceramides [Cer-AP(t18:0/24:0)], and phosphatidylcholines [OxPC(16:0_20:5(2O)], while 100 nM Ang II altered some triglycerides and phosphatidylserines [PS(19:0_22:1). Ang II did not alter the relative expression of several enzymes in lipid metabolism; however, the expression of pyruvate dehydrogenase kinase 2 (PDK2) was increased, and PDK2 can be protective against dyslipidemia. This study is the first to investigate the role of Ang II in colonic epithelial cell metabolism.

Differences in HDL Remodeling during Healthy Pregnancy and Pregnancy with Cardiometabolic Complications

This study investigated the longitudinal trajectory of changes in antioxidative and anti-inflammatory high-density lipoprotein (HDL) components during healthy pregnancy and pregnancy with cardiometabolic complications. We recruited and longitudinally followed 84 women with healthy pregnancies and 46 pregnant women who developed cardiometabolic pregnancy complications (gestational diabetes mellitus and hypertensive disorders of pregnancy). Their general lipid profiles, oxidative stress status, inflammatory status, and antioxidative and anti-inflammatory HDL components were analyzed. The results of our study confirmed the expected trajectory for the routine lipid parameters. Our study results indicate more intensive oxidative stress and a higher level of inflammation in the group with complications compared with the control group. Sphingosine-1-phosphate (S1P) was significantly lower in the first trimester in the group with complications compared with the control group (p < 0.05). We did not find significant differences in the apolipoprotein A1 (Apo A1) concentrations in the first trimester between the control group and the group with complications, but in the second and third trimesters, the group with complications had significantly higher concentrations (p < 0.001, p < 0.05, respectively). The S1P, paraoxonase 1 (PON1), and serum amyloid A (SAA) concentrations were significantly lower in the group with complications in the first trimester. During the second trimester, only the SAA concentrations were identified as significantly lower in the group with complications compared with the control group, while in the third trimester, the PON1, apolipoprotein M (Apo M), and SAA concentrations were all significantly lower in the group with complications. Through a multivariate binary logistic regression analysis, the S1P concentration in the first trimester was distinguished as an HDL-associated marker independently associated with cardiometabolic pregnancy complications. In conclusion, our study results showed that HDL remodeling differs between healthy pregnancies and pregnancies with maternal cardiometabolic complications, with changed HDL composition and functionality consequently impacting its biological functionality in the latter case.

Lipidomic-Based Algorithms Can Enhance Prediction of Obstructive Coronary Artery Disease

Lipidomics emerges as a promising research field with the potential to help in personalized risk stratification and improve our understanding on the functional role of individual lipid species in the metabolic perturbations occurring in coronary artery disease (CAD). This study aimed to utilize a machine learning approach to provide a lipid panel able to identify patients with obstructive CAD. In this posthoc analysis of the prospective CorLipid trial, we investigated the lipid profiles of 146 patients with suspected CAD, divided into two categories based on the existence of obstructive CAD. In total, 517 lipid species were identified, from which 288 lipid species were finally quantified, including glycerophospholipids, glycerolipids, and sphingolipids. Univariate and multivariate statistical analyses have shown significant discrimination between the serum lipidomes of patients with obstructive CAD. Finally, the XGBoost algorithm identified a panel of 17 serum biomarkers (5 sphingolipids, 7 glycerophospholipids, a triacylglycerol, galectin-3, glucose, LDL, and LDH) as totally sensitive (100% sensitivity, 62.1% specificity, 100% negative predictive value) for the prediction of obstructive CAD. Our findings shed light on dysregulated lipid metabolism's role in CAD, validating existing evidence and suggesting promise for novel therapies and improved risk stratification.

Adipocyte-released adipomes in Chagas cardiomyopathy: Impact on cardiac metabolic and immune regulation

Chronic Trypanosoma cruzi infection leads to Chagas cardiomyopathy (CCM), with varying manifestations such as inflammatory hypertrophic cardiomyopathy, arrhythmias, and dilated cardiomyopathy. The factors responsible for the increasing risk of progression to CCM are not fully understood. Previous studies link adipocyte loss to CCM progression, but the mechanism triggering CCM pathogenesis remains unexplored. Our study uncovers that T. cruzi infection triggers adipocyte apoptosis, leading to the release of extracellular vesicles named "adipomes". We developed an innovative method to isolate intact adipomes from infected mice's adipose tissue and plasma, showing they carry unique lipid cargoes. Large and Small adipomes, particularly plasma-derived infection-associated L-adipomes (P-ILA), regulate immunometabolic signaling and induce cardiomyopathy. P-ILA treatment induces hypertrophic cardiomyopathy in wild-type mice and worsens cardiomyopathy severity in post-acute-infected mice by regulating adipogenic/lipogenic and mitochondrial functions. These findings highlight adipomes' pivotal role in promoting inflammation and impairing myocardial function during cardiac remodeling in CD.

Vitamin D and Ceramide Metabolomic Profile in Acute Myocardial Infarction

Sphingolipids (SLs) influence several cellular pathways, while vitamin D exerts many extraskeletal effects in addition to its traditional biological functions, including the modulation of calcium homeostasis and bone health. Moreover, Vitamin D and SLs affect the regulation of each others' metabolism; hence, this study aims to evaluate the relationship between the levels of 25(OH)D and ceramides in acute myocardial infarction (AMI). In particular, the blood abundance of eight ceramides and 25(OH)D was evaluated in 134 AMI patients (aged 68.4 ± 12.0 years, 72% males). A significant inverse correlation between 25(OH)D and both Cer(d18:1/16:0) and Cer(d18:1/18:0) was found; indeed, patients with severe hypovitaminosis D (<10 ng/mL) showed the highest levels of the two investigated ceramides. Moreover, diabetic/dyslipidemic patients with suboptimal levels of 25(OH)D (<30 ng/mL) had higher levels of both the ceramides when compared with the rest of the population. On the other hand, 25(OH)D remained an independent determinant for Cer(d18:1/16:0) (STD Coeff -0.18, t-Value -2, p ≤ 0.05) and Cer(d18:1/18:0) (-0.2, -2.2, p < 0.05). In light of these findings, the crosstalk between sphingolipids and vitamin D may unravel additional mechanisms by which these molecules can influence CV risk in AMI.

Effect of plasma exosome lncRNA on isoproterenol hydrochloride-induced cardiotoxicity in rats

Isoprenaline hydrochloride (IH) is a β-adrenergic receptor agonist commonly used in the treatment of hypotension, shock, asthma, and other diseases. However, IH-induced cardiotoxicity limits its application. A large number of studies have shown that long noncoding RNA (lncRNA) regulates the occurrence and development of cardiovascular diseases. This study aimed to investigate whether abnormal lncRNA expression is involved in IH-mediated cardiotoxicity. First, the Sprague-Dawley (SD) rat myocardial injury model was established. Circulating exosomes were extracted from the plasma of rats and identified. In total, 108 differentially expressed (DE) lncRNAs and 150 DE mRNAs were identified by sequencing. These results indicate that these lncRNAs and mRNAs are substantially involved in chemical cardiotoxicity. Further signaling pathway and functional studies indicated that lncRNAs and mRNAs regulate several biological processes, such as selective mRNA splicing through spliceosomes, participate in sphingolipid metabolic pathways, and play a certain role in the circulatory system. Finally, we obtained 3 upregulated lncRNAs through reverse transcription-quantitative PCR (RT-qPCR) verification and selected target lncRNA-mRNA pairs according to the regulatory relationship of lncRNA/mRNA, some of which were associated with myocardial injury. This study provides valuable insights into the role of lncRNAs as novel biomarkers of chemical-induced cardiotoxicity.

Serum multi-omics analysis in hindlimb unloading mice model: Insights into systemic molecular changes and potential diagnostic and therapeutic biomarkers

Microgravity, in space travel and prolonged bed rest conditions, induces cardiovascular deconditioning along with skeletal muscle mass loss and weakness. The findings of microgravity research may also aid in the understanding and treatment of human health conditions on Earth such as muscle atrophy, and cardiovascular diseases. Due to the paucity of biomarkers and the unknown underlying mechanisms of cardiovascular and skeletal muscle deconditioning in these environments, there are insufficient diagnostic and preventative measures. In this study, we employed hindlimb unloading (HU) mouse model, which mimics astronauts in space and bedridden patients, to first evaluate cardiovascular and skeletal muscle function, followed by proteomics and metabolomics LC-MS/MS-based analysis using serum samples. Three weeks of unloading caused changes in the function of the cardiovascular system in c57/Bl6 mice, as seen by a decrease in mean arterial pressure and heart weight. Unloading for three weeks also changed skeletal muscle function, causing a loss in grip strength in HU mice and atrophy of skeletal muscle indicated by a reduction in muscle mass. These modifications were partially reversed by a two-week recovery period of reloading condition, emphasizing the significance of the recovery process. Proteomics analysis revealed 12 dysregulated proteins among the groups, such as phospholipid transfer protein, Carbonic anhydrase 3, Parvalbumin alpha, Major urinary protein 20 (Mup20), Thrombospondin-1, and Apolipoprotein C-IV. On the other hand, metabolomics analysis showed altered metabolites among the groups such as inosine, hypoxanthine, xanthosine, sphinganine, l-valine, 3,4-Dihydroxyphenylglycol, and l-Glutamic acid. The joint data analysis revealed that HU conditions mainly impacted pathways such as ABC transporters, complement and coagulation cascades, nitrogen metabolism, and purine metabolism. Overall, our results indicate that microgravity environment induces significant alterations in the function, proteins, and metabolites of these mice. These observations suggest the potential utilization of these proteins and metabolites as novel biomarkers for assessing and mitigating cardiovascular and skeletal muscle deconditioning associated with such conditions.

Interplay between Vitamin D and Sphingolipids in Cardiometabolic Diseases

Sphingolipids (SLs) are structural, bioactive molecules with several key cellular roles, whereas 1,25-dihydroxyvitamin D (1,25(OH)D), the active form of vitamin D, is considered the major regulator of calcium homeostasis, although it also exerts other extraskeletal effects. Many studies reported the physiological connection between vitamin D and SLs, highlighting not only the effects of vitamin D on SL metabolism and signaling but also the influence of SLs on vitamin D levels and function, thus strongly suggesting a crosstalk between these molecules. After a brief description of 1,25(OH)D and SL metabolism, this review aims to discuss the preclinical and clinical evidence on the crosstalk between SLs and 1,25(OH)D, with a special focus on cardiometabolic diseases.

Comparative assessment of erythrocyte sphingolipid levels as potential cardiovascular health markers in women from Libya and Serbia: a small-scale study

Aim: Cardiovascular diseases (CVDs) represent the major cause of morbidity and mortality worldwide including Libya, where they account for 43% of all deaths. Sphingolipids are involved in the pathology of numerous diseases including cardiovascular diseases and are proposed as potential biomarkers of cardiovascular health that could be more effective compared to traditional clinical biomarkers. The aim of this study was to determine the sphingolipid content in the erythrocyte membrane of Libyan migrant and Serbian resident women. In addition, to examine if sphingolipid levels could be used as a novel indicator of cardiovascular risk, we evaluated possible correlations with some well-established biomarkers of cardiovascular health.Materials and Methods: A total of 13 Libyan and 15 Serbian healthy women participated in the study. The high-performance version thin-layer chromatography (HPTLC) using the image analysis tool JustTLC was applied for quantification of erythrocytes' sphingolipids.Results: Lower mean values of erythrocytes' sphingolipids and cholesterol concentrations were found in the group of Libyan emigrants compared to Serbian resident women. Besides, in this group of apparently healthy women (n = 28), the sphingolipid content of erythrocytes was inversely related to the Omega-3 index (r =-0.492, p = 0.008) and directly linked to vitamin D status (r = 0.433, p = 0.021) and membrane cholesterol levels (r = 0.474, p = 0.011).Conclusion: The erythrocytes' sphingolipid levels should be measured/assessed as an additional biomarker of CV health, by applying a simple and routine method. Still, further investigation in a larger population-specific context is warranted.

Ceramides and ceramide synthases in cancer: Focus on apoptosis and autophagy

Different studies corroborate a role for ceramide synthases and their downstream products, ceramides, in modulation of apoptosis and autophagy in the context of cancer. These mechanisms of regulation, however, appear to be context dependent in terms of ceramides' fatty acid chain length, subcellular localization, and the presence or absence of their downstream targets. Our current understanding of the role of ceramide synthases and ceramides in regulation of apoptosis and autophagy could be harnessed to pioneer the development of new treatments to activate or inhibit a single type of ceramide synthase, thereby regulating the apoptosis induction or cross talk of apoptosis and autophagy in cancer cells. Moreover, the apoptotic function of ceramide suggests that ceramide analogues can pave the way for the development of novel cancer treatments. Therefore, in the current review paper we discuss the impact of ceramide synthases and ceramides in regulation of apoptosis and autophagy in context of different types of cancers. We also briefly introduce the latest information on ceramide synthase inhibitors, their application in diseases including cancer therapy, and discuss approaches for drug discovery in the field of ceramide synthase inhibitors. We finally discussed strategies for developing strategies to use lipids and ceramides analysis in biological fluids for developing early biomarkers for cancer.

Sphingolipids: From structural components to signaling hubs

In late November 2019, Prof. Lina M. Obeid passed away from cancer, a disease she spent her life researching and studying its intricate molecular underpinnings. Along with her husband, Prof. Yusuf A. Hannun, Obeid laid down the foundations of sphingolipid biochemistry and oversaw its remarkable evolution over the years. Lipids are a class of macromolecules that are primarily associated with cellular architecture. In fact, lipids constitute the perimeter of the cell in such a way that without them, there cannot be cells. Hence, much of the early research on lipids identified the function of this class of biological molecules as merely structural. Nevertheless, unlike proteins, carbohydrates, and nucleic acids, lipids are elaborately diverse as they are not made up of monomers in polymeric forms. This diversity in structure is clearly mirrored by functional pleiotropy. In this chapter, we focus on a major subset of lipids, sphingolipids, and explore their historic rise from merely inert structural components of plasma membranes to lively and necessary signaling molecules that transmit various signals and control many cellular processes. We will emphasize the works of Lina Obeid since she was an integral pillar of the sphingolipid research world.

The therapeutic potential of sphingolipids for cardiovascular diseases

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide and Inflammation plays a critical role in the development of CVD. Despite considerable progress in understanding the underlying mechanisms and various treatment options available, significant gaps in therapy necessitate the identification of novel therapeutic targets. Sphingolipids are a family of lipids that have gained attention in recent years as important players in CVDs and the inflammatory processes that underlie their development. As preclinical studies have shown that targeting sphingolipids can modulate inflammation and ameliorate CVDs, targeting sphingolipids has emerged as a promising therapeutic strategy. This review discusses the current understanding of sphingolipids' involvement in inflammation and cardiovascular diseases, the existing therapeutic approaches and gaps in therapy, and explores the potential of sphingolipids-based drugs as a future avenue for CVD treatment.

Ceramide in cerebrovascular diseases

Ceramide, a bioactive sphingolipid, serves as an important second messenger in cell signal transduction. Under stressful conditions, it can be generated from de novo synthesis, sphingomyelin hydrolysis, and/or the salvage pathway. The brain is rich in lipids, and abnormal lipid levels are associated with a variety of brain disorders. Cerebrovascular diseases, which are mainly caused by abnormal cerebral blood flow and secondary neurological injury, are the leading causes of death and disability worldwide. There is a growing body of evidence for a close connection between elevated ceramide levels and cerebrovascular diseases, especially stroke and cerebral small vessel disease (CSVD). The increased ceramide has broad effects on different types of brain cells, including endothelial cells, microglia, and neurons. Therefore, strategies that reduce ceramide synthesis, such as modifying sphingomyelinase activity or the rate-limiting enzyme of the de novo synthesis pathway, serine palmitoyltransferase, may represent novel and promising therapeutic approaches to prevent or treat cerebrovascular injury-related diseases.

Role of ceramides in diabetic foot ulcers (Review)

Diabetes mellitus (DM) is a metabolic disorder, which if not managed properly, can lead to serious health problems over time and impose significant financial burden on the patient, their family and society as a whole. The study of this disease and the underlying biological mechanism is gaining momentum. Multiple pieces of conclusive evidence show that ceramides are involved in the occurrence and development of diabetes. The present review focuses on the function of ceramides, a type of sphingolipid signaling molecule, to provide a brief description of ceramides and their metabolism, discuss the significant roles of ceramides in the healthy skin barrier, and speculate on the potential involvement of ceramides in the pathogenesis and development of diabetic foot ulcers (DFUs). Understanding these aspects of this disease more thoroughly is crucial to establish how ceramides contribute to the etiology of diabetic foot infections and identify possible therapeutic targets for the treatment of DFUs.

Sphingolipids and Atherosclerosis: The Dual Role of Ceramide and Sphingosine-1-Phosphate

Sphingolipids are bioactive molecules that play either pro- and anti-atherogenic roles in the formation and maturation of atherosclerotic plaques. Among SLs, ceramide and sphingosine-1-phosphate showed antithetic properties in regulating various molecular mechanisms and have emerged as novel potential targets for regulating the development of atherosclerosis. In particular, maintaining the balance of the so-called ceramide/S1P rheostat is important to prevent the occurrence of endothelial dysfunction, which is the trigger for the entire atherosclerotic process and is strongly associated with increased oxidative stress. In addition, these two sphingolipids, together with many other sphingolipid mediators, are directly involved in the progression of atherogenesis and the formation of atherosclerotic plaques by promoting the oxidation of low-density lipoproteins (LDL) and influencing the vascular smooth muscle cell phenotype. The modulation of ceramide and S1P levels may therefore allow the development of new antioxidant therapies that can prevent or at least impair the onset of atherogenesis, which would ultimately improve the quality of life of patients with coronary artery disease and significantly reduce their mortality.

Targeted Sphingolipid Analysis in Heart, Gizzard, and Breast Muscle in Chickens Reveals Possible New Target Organs of Fumonisins

Alteration of sphingolipid synthesis is a key event in fumonisins toxicity, but only limited data have been reported regarding the effects of fumonisins on the sphingolipidome. Recent studies in chickens found that the changes in sphingolipids in liver, kidney, lung, and brain differed greatly. This study aimed to determine the effects of fumonisins on sphingolipids in heart, gizzard, and breast muscle in chickens fed 20.8 mg FB1 + FB2/kg for 9 days. A significant increase in the sphinganine:sphingosine ratio due to an increase in sphinganine was observed in heart and gizzard. Dihydroceramides and ceramides increased in the hearts of chickens fed fumonisins, but decreased in the gizzard. The dihydrosphingomyelin, sphingomyelin, and glycosylceramide concentrations paralleled those of ceramides, although the effects were less pronounced. In the heart, sphingolipids with fatty acid chain lengths of 20 to 26 carbons were more affected than those with 14-16 carbons; this difference was not observed in the gizzard. Partial least squares-discriminant analysis on sphingolipids in the heart allowed chickens to be divided into two distinct groups according to their diet. The same was the case for the gizzard. Pearson coefficients of correlation among all the sphingolipids assayed revealed strong positive correlations in the hearts of chickens fed fumonisins compared to chickens fed a control diet, as well as compared to gizzard, irrespective of the diet fed. By contrast, no effect of fumonisins was observed on sphingolipids in breast muscle.