Gliomas are the largest category of primary malignant brain tumors in adults, and glioblastomas account for nearly half of malignant gliomas. Glioblastomas are notoriously aggressive and drug-resistant, with a very poor 5 year survival rate of about 5%. New approaches to treatment are thus urgently needed.
View Article and Find Full Text PDFLittle is known about an oncogenic signal transducer β-1,4-galactosyltransferase-V (β-1,4-GalT-V), in human colorectal cancer. Using quantitative RT-PCR, immunohistochemical staining and ELISA assays, we determined that β-1,4-GalT-V gene/protein expression is specifically increased in human colorectal cancer (CRC) tumors, compared to visibly normal tissue. Furthermore, we observed a marked increase in its enzymatic activity, and its product lactosylceramide.
View Article and Find Full Text PDFAccumulating evidence suggests that α-synuclein (α-syn) occurs physiologically as a helically folded tetramer that resists aggregation. However, the mechanisms underlying the regulation of formation of α-syn tetramers are still mostly unknown. Cellular membrane lipids are thought to play an important role in the regulation of α-syn tetramer formation.
View Article and Find Full Text PDFObjective: To evaluate interictal, circulating sphingolipids in women migraineurs.
Methods: In the fasting state, serum samples were obtained pain-free from 88 women with episodic migraine (EM; n=52) and from controls (n=36). Sphingolipids were detected and quantified by high-performance liquid chromatography coupled with tandem mass spectrometry using multiple reaction monitoring.
Ceramide is a bioactive lipid that plays an important role in stress responses leading to apoptosis, cell growth arrest and differentiation. Ceramide production is due in part to sphingomyelin hydrolysis by sphingomyelinases. In brain, neutral sphingomyelinase 2 (nSMase2) is expressed in neurons and increases in its activity and expression have been associated with pro-inflammatory conditions observed in Alzheimer's disease, multiple sclerosis and human immunodeficiency virus (HIV-1) patients.
View Article and Find Full Text PDFModification of hypothalamic fatty acid (FA) metabolism can improve energy homeostasis and prevent hyperphagia and excessive weight gain in diet-induced obesity (DIO) from a diet high in saturated fatty acids. We have shown previously that C75, a stimulator of carnitine palmitoyl transferase-1 (CPT-1) and fatty acid oxidation (FAOx), exerts at least some of its hypophagic effects via neuronal mechanisms in the hypothalamus. In the present work, we characterized the effects of C75 and another anorexigenic compound, the glycerol-3-phosphate acyltransferase (GPAT) inhibitor FSG67, on FA metabolism, metabolomics profiles, and metabolic stress responses in cultured hypothalamic neurons and hypothalamic neuronal cell lines during lipid excess with palmitate.
View Article and Find Full Text PDFSphingomyelin metabolism has been linked to several diseases and to longevity. However, few epidemiological studies have quantified individual plasma sphingomyelin species (identified by acyl-chain length and saturation) or their relationship between demographic factors and disease processes. In this study, we determined plasma concentrations of distinct sphingomyelin species in 992 individuals, aged 55 and older, enrolled in the Baltimore Longitudinal Study of Aging.
View Article and Find Full Text PDFCellular studies suggest sphingolipids may cause or accelerate amyloid-beta (Aβ) and tau pathology but in vivo human studies are lacking. We determined cerebrospinal fluid levels of sphingolipids (ceramides and sphingomyelins), amyloid-beta (Aβ1-42, AβX-38, AβX-40, and AβX-42) and tau (T-tau and p-tau181) in 91 cognitively normal individuals, aged 36-69 years, with a parental history of Alzheimer's disease. The 18-carbon acyl chain length ceramide species was associated with AβX-38 (r = 0.
View Article and Find Full Text PDFAxonal damage is a prominent cause of disability and yet its pathogenesis is incompletely understood. Using a xenogeneic system, here we define the bioenergetic changes induced in rat neurons by exposure to cerebrospinal fluid samples from patients with multiple sclerosis compared to control subjects. A first discovery cohort of cerebrospinal fluid from 13 patients with multiple sclerosis and 10 control subjects showed that acute exposure to cerebrospinal fluid from patients with multiple sclerosis induced oxidative stress and decreased expression of neuroprotective genes, while increasing expression of genes involved in lipid signalling and in the response to oxidative stress.
View Article and Find Full Text PDFBackground: Coronary artery disease (CAD) is associated with verbal memory decline, although deterioration may be mitigated in individuals undertaking exercise interventions. Ceramide sphingolipids, suggested to play a role in pathological neurodegeneration, have been associated with the development and progression of CAD but their relationship with cognitive response to exercise has not been assessed. In this study, concentrations of very long chain ceramides (C22:0 and C24:0) were assessed as predictors of changes in verbal memory performance over 1 year in subjects with CAD undertaking cardiac rehabilitation (CR).
View Article and Find Full Text PDFJ Neuroimmune Pharmacol
December 2013
The development and application of biomarkers to neurodegenerative diseases has become increasingly important in clinical practice and therapeutic trials. While substantial progress has been made at the basic science level in understanding the pathophysiology of HIV-Associated Neurocognitive Disorders (HAND), there are significant limitations in our current ability to predict the onset or trajectory of disease, and to accurately determine the effects of therapeutic interventions. Thus, the development of objective biomarkers is critical to further our understanding and treatment of HAND.
View Article and Find Full Text PDFBackground: Mutations in the gene coding for glucocerebrosidase (GBA), which metabolizes glucosylceramide (a monohexosylceramide) into glucose and ceramide, is the most common genetic risk factor for sporadic Parkinson's disease (PD). GBA mutation carriers are more likely to have an earlier age of onset and to develop cognitive impairment and dementia. We hypothesized that plasma levels of lipids involved in ceramide metabolism would also be altered in PD non-GBA mutation carriers and associated with worse cognition.
View Article and Find Full Text PDFDespite wide spread use of combination antiretroviral therapy (cART) in developed countries, approximately half of HIV-infected patients will develop impairments in cognitive function. Accumulating evidence suggests that neuronal dysfunction can be precipitated by HIV-infection of macrophages by mechanisms that involve alterations in innate and adaptive immune responses. HIV-infection of macrophages is known to increase the release of soluble neurotoxins.
View Article and Find Full Text PDFIn a xenograft model wherein, live renal cancer cells were implanted under the kidney capsule in mice, revealed a 30-fold increase in tumor volume over a period of 26 days and this was accompanied with a 32-fold increase in the level of lactosylceramide (LacCer). Mice fed D- threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP), an inhibitor of glucosylceramide synthase and lactosylceramide synthase (LCS: β-1,4-GalT-V), showed marked reduction in tumor volume. This was accompanied by a decrease in the mass of lactosylceramide and an increase in glucosylceramide (GlcCer) level.
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