Dynamics of long polyunsaturated fatty acids in rat brain

Unhealthy dietary habit e.g. lipid rich diet could result in inflammatory processes and necrosis in the gastrointestinal tract in which free radical reactions are involved. Higher plants have many free radical scavenger molecules and anti-inflammatory compounds in wonderful variations. Sempervivum tectorum L. is well known plant in folk medicine. In the case of complex plant extracts, such as Sempervivum tectorum ones, which contain several active compounds, it is impossible to discover the single mechanism of action, therefore practically the reducing activity have to be measured in vitro and in rat intestinal tract in vivo. The question was, whether the absorbed active compounds of Sempervivum tectorum extract were able to influence on the changed cellular redox states in mucosa of all part of intestinal tract in experimental bowel disease. This biochemical work presents the protective effect of natural polyphenols and flavonoids of Sempervivum tectorum extract in bowel disease - especially in jejunum and ileum - induced by high dietary triglyceride and cholesterol level in rats

Mass spectrometry coupled to imaging techniques: The better the view the greater the challenge

These are definitively exciting times for membrane lipid researchers. Once considered just as the cell membrane building blocks, the important role these lipids play is steadily being acknowledged. The improvement occurred in mass spectrometry techniques (MS) allows the establishment of the precise lipid composition of biological extracts. However, to fully understand the biological function of each individual lipid species, we need to know its spatial distribution and dynamics. In the past 10 years, the field has experienced a profound revolution thanks to the development of MS-based techniques allowing lipid imaging (MSI). Images reveal and verify what many lipid researchers had already shown by different means, but none as convincing as an image: each cell type presents a specific lipid composition, which is highly sensitive to its physiological and pathological state. While these techniques will help to place membrane lipids in the position they deserve, they also open the black box containing all the unknown regulatory mechanisms accounting for such tailored lipid composition. Thus, these results urges to different disciplines to redefine their paradigm of study by including the complexity revealed by the MSI techniques.This work was supported by the Instituto Carlos III (Ministerio de Economía y Competitividad) CP12/03338, Gwendolyn Barceló-Coblijn holds a “Miguel Servet” contract from the Instituto Carlos III. Technical support and personnel provided by the Servicio de Lipidómica of the SGIKER (UPV/EHU, MICINN, GV/E.G., ESF) is gratefully acknowledged

Polyunsaturated Fatty Acid-Enriched Lipid Fingerprint of Glioblastoma Proliferative Regions Is Differentially Regulated According to Glioblastoma Molecular Subtype

Glioblastoma (GBM) represents one of the deadliest tumors owing to a lack of effective treatments. The adverse outcomes are worsened by high rates of treatment discontinuation, caused by the severe side effects of temozolomide (TMZ), the reference treatment. Therefore, understanding TMZ’s effects on GBM and healthy brain tissue could reveal new approaches to address chemotherapy side effects. In this context, we have previously demonstrated the membrane lipidome is highly cell type-specific and very sensitive to pathophysiological states. However, little remains known as to how membrane lipids participate in GBM onset and progression. Hence, we employed an ex vivo model to assess the impact of TMZ treatment on healthy and GBM lipidome, which was established through imaging mass spectrometry techniques. This approach revealed that bioactive lipid metabolic hubs (phosphatidylinositol and phosphatidylethanolamine plasmalogen species) were altered in healthy brain tissue treated with TMZ. To better understand these changes, we interrogated RNA expression and DNA methylation datasets of the Cancer Genome Atlas database. The results enabled GBM subtypes and patient survival to be linked with the expression of enzymes accounting for the observed lipidome, thus proving that exploring the lipid changes could reveal promising therapeutic approaches for GBM, and ways to ameliorate TMZ side effects.This study was supported in part by the Research Unit of the University Hospital Son Espases (“Ajuts a la Investigació de l’Hospital Son Espases 2017—Aplicación del lipidoma en el diagnóstico, pronóstico y tratamiento del glioma”), Basque Government (IT1162-19), the Institute of Health Carlos III (PI16/02200), and the EC (European Regional Development Fund, ERDF, CP12/03338). A.M.B. and J.B-E. hold predoctoral fellowships of the Govern Balear (Direcció General d’Innovació i Recerca, FPI/2160/2018 and FPI/1787/2015, respectively), co-funded by the ESF (European Social Fund). K.P.-R. contract was supported by the Govern Balear (Servei d’Ocupació de les IIles Balears and Garantia Juvenil, JQ-SP 18/17), co-funded by the ESF. G.B.-C.’s was supported by the Institute of Health Carlos III, co-funded by ERDF (Miguel Servet II program, CPII17/00005)

A Drastic Shift in Lipid Adducts in Colon Cancer Detected by MALDI-IMS Exposes Alterations in Specific K+ Channels

Even though colorectal cancer (CRC) is one of the most preventable cancers, it is one of the deadliest, and recent data show that the incidence in people <50 years has unexpectedly increased. While new techniques for CRC molecular classification are emerging, no molecular feature is as yet firmly associated with prognosis. Imaging mass spectrometry (IMS) lipidomic analyses have demonstrated the specificity of the lipid fingerprint in differentiating pathological from healthy tissues. During IMS lipidomic analysis, the formation of ionic adducts is common. Of particular interest is the [Na+]/[K+] adduct ratio, which already functions as a biomarker for homeostatic alterations. Herein, we show a drastic shift of the [Na+]/[K+] adduct ratio in adenomatous colon mucosa compared to healthy mucosa, suggesting a robust increase in K+ levels. Interrogating public databases, a strong association was found between poor diagnosis and voltage-gated potassium channel subunit beta-2 (KCNAB2) overexpression. We found this overexpression in three CRC molecular subtypes defined by the CRC Subtyping Consortium, making KCNAB2 an interesting pharmacological target. Consistently, its pharmacological inhibition resulted in a dramatic halt in commercial CRC cell proliferation. Identification of potential pharmacologic targets using lipid adduct information emphasizes the great potential of IMS lipidomic techniques in the clinical field.This study was supported in part by the Institute of Health Carlos III (CP12/03338 and PI16/02200), Basque Government (IT1162-19), and the EC (European Regional Development Fund, ERDF, CP12/03338). A.M.B. and J.B-E. hold predoctoral fellowships of the Govern Balear (Direcció General d’Innovació i Recerca, FPI/2160/2018 and FPI/1787/2015, respectively), co-funded by the ESF (European Social Fund). K.P.-R. contract was supported by the Govern Balear (Servei d’Ocupació de les IIles Balears and Garantia Juvenil, JQ-SP 18/17), co-funded by the ESF. G.B.-C. and D.H.L.’s contracts were supported by the Institute of Health Carlos III, co-funded by ERDF (Miguel Servet II program, CPII17/00005 and PI16/02200, respectively). We are grateful to SGiker Lipidomic Service (UPV/EHU, MICINN, GV/EG, ESF) for the expert advice and technical and human support in MALDI-IMS analysis. The publication fee in this Open Access journal is fully supported by the Liberi Call of the IdISBa

P465L pparγ mutation confers partial resistance to the hypolipidemic action of fibrates.

Familial partial lipodystrophic syndrome 3 (FPLD3) is associated with mutations in the transcription factor PPAR. The P467L mutant confers a dominant negative effect. We have previously investigated the pathophysiology of FPLD3 using a humanised mouse harbouring an equivalent mutation (P465L) in PPAR that recapitulated the human clinical phenotype. One of the key clinical manifestations observed in humans and mice is the accumulation of fat in the liver. Here, we dissect the molecular mechanisms that facilitate accumulation of lipids in the liver and characterise the negative effect of the PPAR mutation on the activation of PPAR in vivo by fibrates. P465L mice have increased insulin and FFAs, decreased secretion of VLDL when fed HFD and impaired hypolipidemic response to WY14643. Thus, the phenotype of PPAR mutations may synergise with defects on PPAR function, indicating that the phenotype of the FPLD3 patients may not only be attributed to the dysfunction of PPAR

Normalization of sphingomyelin levels by 2-hydroxyoleic acid induces autophagic cell death of SF767 cancer cells

The very high mortality rate of gliomas reflects the unmet therapeutic need associated with this type of brain tumor. We have discovered that the plasma membrane fulfills a critical role in the propagation of tumorigenic signals, whereby changes in membrane lipid content can either activate or silence relevant pathways. We have designed a synthetic fatty acid, 2-hydroxyoleic acid (2OHOA), that specifically activates sphingomyelin synthase (SGMS), thereby modifying the lipid content of cancer cell membranes and restoring lipid levels to those found in normal cells. In reverting, the structure of the membrane by activating SGMS, 2OHOA inhibits the RAS-MAPK pathway, which in turn fails to activate the CCND (Cyclin D)-CDK4/CDK6 and PI3K-AKT1 pathways. The overall result in SF767 cancer cells, a line that is resistant to apoptosis, is the sequential induction of cell cycle arrest, cell differentiation and autophagy. Such effects are not observed in normal cells (MRC-5) and thus, this specific activation of programmed cell death infers greater efficacy and lower toxicity to 2OHOA than that associated with temozolomide (TMZ), the reference drug for the treatment of glioma

2-Hydroxyoleate, a nontoxic membrane binding anticancer drug, induces glioma cell differentiation and autophagy

Despite recent advances in the development of new cancer therapies, the treatment options for glioma remain limited, and the survival rate of patients has changed little over the past three decades. Here, we show that 2-hydroxyoleic acid (2OHOA) induces differentiation and autophagy of human glioma cells. Compared to the current reference drug for this condition, temozolomide (TMZ), 2OHOA combated glioma more efficiently and, unlike TMZ, tumor relapse was not observed following 2OHOA treatment. The novel mechanism of action of 2OHOA is associated with important changes in membrane-lipid composition, primarily a recovery of sphingomyelin (SM) levels, which is markedly low in glioma cells before treatment. Parallel to membrane-lipid regulation, treatment with 2OHOA induced a dramatic translocation of Ras from the membrane to the cytoplasm, which inhibited the MAP kinase pathway, reduced activity of the PI3K/Akt pathway, and downregulated Cyclin D-CDK4/6 proteins followed by hypophosphorylation of the retinoblastoma protein (RB). These regulatory effects were associated with induction of glioma cell differentiation into mature glial cells followed by autophagic cell death. Given its high efficacy, low toxicity, ease of oral administration, and good distribution to the brain, 2OHOA constitutes a new and potentially valuable therapeutic tool for glioma patients

The Interplay of Microbiome and Immune Response in Health and Diseases

[Increasing evidence suggests that microbiota and especially the gut microbiota (the microbes inhabiting the gut including bacteria, archaea, viruses, and fungi) plays a key role in human physiology and pathology. Recent findings indicate how dysbiosis—an imbalance in the composition and organization of microbial populations—could severely impact the development of different medical conditions (from metabolic to mood disorders), providing new insights into the comprehension of diverse diseases, such as IBD, obesity, asthma, autism, stroke, diabetes, and cancer. Given that microbial cells in the gut outnumber host cells, microbiota influences human physiology both functionally and structurally. Microbial metabolites bridge various—even distant—areas of the organism by way of the immune and hormone system. For instance, it is now clear that the mutual interaction between the gastrointestinal tract and the brain (gut–brain axis), often involves gut microbiota, indicating that the crosstalk between the organism and its microbial residents represents a fundamental aspect of both the establishment and maintenance of healthy conditions. Moreover, it is crucial to recognize that beyond the intestinal tract, microbiota populates other host organs and tissues (e.g., skin and oral mucosa). We have edited this eBook with the aim of publishing manuscripts focusing on the impact of microbiota in the development of different diseases and their associated treatments.