Lipidomics is a rapidly growing field, fueled by developments in analytical instrumentation and bioinformatics. To date, most researchers and industries have employed their own lipidomics workflows without a consensus on best practices. Without a community-wide consensus on best practices for the prevention of lipid degradation and transformations through sample collection and analysis, it is difficult to assess the quality of lipidomics data and hence trust results. Clinical studies often rely on samples being stored for weeks or months until they are analyzed, but inappropriate sampling techniques, storage temperatures, and analytical protocols can result in the degradation of complex lipids and the generation of oxidized or hydrolyzed metabolite artifacts. While best practices for lipid stability are sample dependent, it is generally recommended that strategies during sample preparation capable of quenching enzymatic activity and preventing oxidation should be considered. In addition, after sample preparation, lipid extracts should be stored in organic solvents with antioxidants at -20 °C or lower in an airtight container without exposure to light or oxygen. This will reduce or eliminate sublimation, and chemically and physically induced molecular transformations such as oxidation, enzymatic transformation, and photon/heat-induced degradation. This review explores the available literature on lipid stability, with a particular focus on human health and/or clinical lipidomic applications. Specifically, this includes a description of known mechanisms of lipid degradation, strategies, and considerations for lipid storage, as well as current efforts for standardization and quality insurance of protocols.

A Review of Efforts to Improve Lipid Stability during Sample Preparation and Standardization Efforts to Ensure Accuracy in the Reporting of Lipid Measurements.

Insights for Alzheimer's disease pharmacotherapy and current clinical trials

Progress in Detection of Biomarker of Ovarian Cancer: Lysophosphatidic Acid

Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disease with insulin deficiency due to pancreatic β cell destruction. Multiple independent cohort studies revealed specific lipid spectrum alterations prior to islet autoimmunity in T1DM. Except for serving as building blocks for membrane biogenesis, accumulative evidence suggests lipids and their derivatives can also modulate different biological processes in the progression of T1DM, such as inflammation responses, immune attacks, and β cell vulnerability. However, the types of lipids are huge and majority of them have been largely unexplored in T1DM. In this review, based on the lipid classification system, we summarize the clinical evidence on dyslipidemia related to T1DM and elucidate the potential mechanisms by which they participate in regulating inflammation responses, modulating lymphocyte function and influencing β cell susceptibility to apoptosis and dysfunction. This review systematically recapitulates the role and mechanisms of various lipids in T1DM, providing new therapeutic approaches for T1DM from a nutritional perspective.

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Lipid metabolism in type 1 diabetes mellitus: Pathogenetic and therapeutic implications

The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory distress syndrome coronavirus 2 (SARS-Cov-2), was identified for the first time in late 2019 in China, resulting in a global pandemic of massive impact. Despite a fast development and implementation of vaccination strategies, and the scouting of several pharmacological treatments, alternative effective treatments are still needed. In this regard, cannabinoids represent a promising approach because they have been proven to exhibit several immunomodulatory, anti-inflammatory, and antiviral properties in COVID-19 disease models and related pathological conditions. This mini-review aims at providing a practical brief overview of the potential applications of cannabinoids so far identified for the treatment and prevention of COVID-19, finally considering key aspects related to their technological and clinical implementation.

Cannabinoids as Emergent Therapy Against COVID-19.

Lysophosphatidic acids (lysoPtdOH) are involved in several physiological processes including cell proliferation, inflammation, and glucose metabolism. However, measuring lysoPtdOH is challenging due to inadequate extraction techniques, poor chromatographic resolution, or the inability to discriminate between sn-1 and sn-2 regioisomers. In the present work, we developed a high-throughput (10 min run times) ultra-high-performance liquid chromatography-tandem mass spectrometry method capable of discriminating lysoPtdOH species by their fatty acyl composition and sn-localization on glycerol backbones. We quantitated sn-1/sn-2 regioisomeric pairs of lysoPtdOH with 16:0, 18:0, 18:1, 18:2, 20:4, and 22:6 fatty acyl chains using 50 μL of mouse plasma. The method presented here can be expanded to profile more lysoPtdOH species, and has the potential to be used in clinical settings to quickly screen lysoPtdOH profiles. Finally, the ability to discriminate between sn-1 and sn-2 isomers can provide insights regarding the metabolic origins and fates of specific lysoPtdOH molecules.

Development of a Rapid Ultra High-Performance Liquid Chromatography/Tandem Mass Spectrometry Method for the Analysis of sn-1 and sn-2 Lysophosphatidic Acid Regioisomers in Mouse Plasma

To study effects on cellular innate immune responses to ORF8, ORF10, and Membrane protein (M protein) from the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes COVID-19, in combination with cannabidiol (CBD). HEK293 cells transfected with plasmids expressing control vector, ORF8, ORF10, or M protein were assayed for cell number and markers of apoptosis at 24 h, and interferon and interferon-stimulated gene expression at 14 h, with or without CBD. Cells transfected with polyinosinic:polycytidylic acid (Poly (I:C)) were also studied as a general model of RNA-type viral infection. Reduced cell number and increased early and late apoptosis were found when expression of viral genes was combined with 1–2 μM CBD treatment, but not in control-transfected cells treated with CBD, or in cells expressing viral genes but treated only with vehicle. In cells expressing viral genes, CBD augmented expression of IFNγ, IFNλ1 and IFNλ2/3, as well as the 2′-5′-oligoadenylate synthetase (OAS) family members OAS1, OAS2, OAS3, and OASL. CBD also augmented expression of these genes in control cells not expressing viral genes, but without enhancing apoptosis. CBD similarly enhanced the cellular anti-viral response to Poly (I:C). Our results demonstrate a poor ability of HEK293 cells to respond to SARS-CoV-2 genes alone, but an augmented innate anti-viral response to these genes in the presence of CBD. Thus, CBD may prime components of the innate immune system, increasing readiness to respond to RNA-type viral infection without activating apoptosis, and could be studied for potential in prophylaxis. 

https://doi.org/10.1016/j.lfs.2022.120624

Effect of cannabidiol on apoptosis and cellular interferon and interferon-stimulated gene responses to the SARS-CoV-2 genes ORF8, ORF10 and M protein

We have previously reported deficits in phospholipids and NMDA-receptors in brains of 2–3 month-old mice deficient in the mitochondrial enzyme lysophosphatidic acid acyltransferase delta (LPAATδ)/acylglycerophosphate acyltransferase 4 (AGPAT4), which were associated with deficits in learning and memory. An initial assessment suggested these mice may also be predisposed to an anxiogenic-like behavioral phenotype, but this was not fully evident in young mice. Since some animal and human studies report worsening anxiety from middle-to-older adulthood, we hypothesized that aging may reveal a significant anxiety-like phenotype in Lpaatδ-deficient mice. We analyzed anxiety-like behavior in 14- and 20-month old Lpaatδ deficient (Lpaatδ−/−) mice and their wildtype age-matched littermate controls. Fourteen month-old Lpaatδ-deficient mice had ∼3-fold greater rearing activity over 24-h than controls. Aging was associated with a significant decrease in rearing activity in Lpaatδ-deficient mice, but not in wildtype control mice. However, rearing activity remained 59% higher in Lpaatδ-deficient mice than controls at 20 months of age. Behavior of Lpaatδ-deficient mice in the open field test and elevated plus maze also suggested a more anxiogenic-like phenotype, although differences between the genotypes were statistically significant only at 20 months. Brain NMDA receptor subunits were not significantly different between different ages or genotypes, which differed from prior results in younger mice. An initial screen of genes related to behavior indicated lower brain expression in Lpaatδ-deficient mice of the serotonin metabolism genes 5htr1a and slc6a4. These studies have implications for understanding associations between LPAATδ/AGPAT4 gene variants and human anxiety.

Age-associated increase in anxiety-like behavior in Lpaatδ/Agpat4 knockout mice

Glucagon-like peptide-1 (GLP-1) potentiates glucose-stimulated insulin secretion (GSIS). While dozens of compounds stimulate GLP-1 secretion, few inhibit. Reduced GLP-1 secretion and impaired GSIS occur in chronic inflammation. Lysophosphatidic acids (LPAs) are bioactive phospholipids elevated in inflammation. The aim of this study was to test whether LPA inhibits GLP-1 secretion in vitro and in vivo. GLUTag L-cells were treated with various LPA species, with or without LPA receptor (LPAR) antagonists, and media GLP-1 levels, cellular cyclic AMP and calcium ion concentrations, and DPP4 activity levels were analyzed. Mice were injected with LPA, with or without LPAR antagonists, and serum GLP-1 and DPP4 activity were measured. GLUTag GLP-1 secretion was decreased ~70–90% by various LPAs. GLUTag expression of Lpar1, 2, and 3 was orders of magnitude higher than Lpar4, 5, and 6, implicating the former group in this effect. In agreement, inhibition of GLP-1 secretion was reversed by the LPAR1/3 antagonist Ki16425, the LPAR1 antagonists AM095 and AM966, or the LPAR2 antagonist LPA2-antagonist 1. We hypothesized involvement of Gαi-mediated LPAR activity, and found that intracellular cyclic AMP and calcium ion concentrations were decreased by LPA, but restored by Ki16425. Mouse LPA injection caused an ~50% fall in circulating GLP-1, although only LPAR1 or LPAR1/3 antagonists, but not LPAR2 antagonism, prevented this. GLUTag L-cell and mouse serum DPP4 activity was unchanged by LPA or LPAR antagonists. LPA therefore impairs GLP-1 secretion in vitro and in vivo through Gαi-coupled LPAR1/3 signaling, providing a new mechanism linking inflammation with impaired GSIS.

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Glucagon-like Peptide-1 Secretion Is Inhibited by Lysophosphatidic Acid

Abstract Barth syndrome (BTHS) is caused by mutations in the TAZ gene encoding the cardiolipin remodeling enzyme, Tafazzin. The study objective was to quantitatively examine growth characteristics and mitochondrial morphology of transformed lymphoblast cell lines derived from five patients with BTHS relative to five healthy controls, as well as the therapeutic potential of oleoylethanolamide (OEA) and linoleoylethanolamide (LEA). These bioactive lipids both activate PPARα, which may be therapeutic. BTHS lymphoblasts grew more slowly than controls, suggesting lymphopenia merits clinical investigation. Treatment of BTHS lymphoblasts with OEA, but not LEA, significantly restored mitochondrial membrane potential, as well as colony growth in all BTHS lymphoblast lines, although a full growth rescue was not achieved. Quantification analysis of electron micrographs from three BTHS and healthy lymphoblast donors indicated similar numbers of mitochondria per cell, but lower average cristae length per mitochondrion, and higher mitochondrial density. Additionally, BTHS lymphoblasts had larger mitochondria, and a higher percentage of abnormally large mitochondria (&gt; 1 μm 2 ) than healthy controls. Notably, OEA treatment significantly restored mitochondrial size, without affecting density or cristae lengths. Cardiolipin total content, relative linoleic acid content and monolysocardiolipin:cardiolipin ratios were not improved by OEA, indicating that effects on growth, and mitochondrial morphology and function, occurred without resolving this deficit. However, immunoblotting showed higher levels of OPA1, a biomarker for mitochondrial fusion, in BTHS lymphoblasts, which was attenuated by OEA treatment, implicating altered mitochondrial dynamics in the pathology and treatment of BTHS. 

/pdf/n-oleoylethanolamide-treatment-of-lymphoblasts-deficient-in-2ixwwtjt.pdf

Maria F. Fernandes

Papers

Development of a Rapid Ultra High-Performance Liquid Chromatography/Tandem Mass Spectrometry Method for the Analysis of sn-1 and sn-2 Lysophosphatidic Acid Regioisomers in Mouse Plasma

Effect of cannabidiol on apoptosis and cellular interferon and interferon-stimulated gene responses to the SARS-CoV-2 genes ORF8, ORF10 and M protein

Age-associated increase in anxiety-like behavior in Lpaatδ/Agpat4 knockout mice

Glucagon-like Peptide-1 Secretion Is Inhibited by Lysophosphatidic Acid

N-oleoylethanolamide treatment of lymphoblasts deficient in Tafazzin improves cell growth and mitochondrial morphology and dynamics