Changes in Lipid Composition During Manganese-Induced Apoptosis in PC12 Cells.

Lipid composition of membranes is fundamental to modulate signaling pathways relying on lipid metabolites and/or membrane proteins, thus resulting in the regulation of important cell processes such as apoptosis. In this case, membrane remodeling is an early event important for the activation of signaling leading to cell death and removal of apoptotic cells. In the present study, we analyzed phospholipid, cholesterol and fatty acid content during apoptosis induced by manganese in PC12 cells. Lipid analysis of whole cells and detergent-resistant membranes was carried out by HPLC/GC. Results showed that apoptosis is associated with changes in lipid composition detectable in whole cell extracts, namely cholesterol, phosphatidylserine and phosphatidylethanolamine decreases. Noteworthy, phosphatidylserine level reduction was detectable before to the detection of apoptosis, in correlation with our previous study carried out by radioactive labelling. By contrast, phosphatidylserine and phosphatidylethanolamine changes were not detected in detergent resistant membranes, which instead showed an altered composition in phosphatidylinositol, phosphatidylcholine and sphingomyelin in apoptotic cells.

Atomic force microscopy imaging of lipid rafts of human breast cancer cells.

Several studies suggest that the plasma membrane is composed of micro-domains of saturated lipids that segregate together to form lipid rafts. Lipid rafts have been operationally defined as cholesterol- and sphingolipid-enriched membrane micro-domains resistant to solubilization by non-ionic detergents at low temperatures. Here we report a biophysical approach aimed at investigating lipid rafts of MDA-MB-231 human breast cancer cells by coupling an atomic force microscopy (AFM) study to biochemical assays namely Western blotting and high performance thin layer chromatography. Lipid rafts were purified by ultracentrifugation on discontinuous sucrose gradient using extraction with Triton X-100. Biochemical analyses proved that the fractions isolated at the 5% and 30% sucrose interface (fractions 5 and 6) have a higher content of cholesterol, sphingomyelin and flotillin-1 with respect to the other purified fractions. Tapping mode AFM imaging of fraction 5 showed membrane patches whose height corresponds to the one awaited for a single lipid bilayer as well as the presence of micro-domains with lateral dimensions in the order of a few hundreds of nanometers. In addition, an AFM study using specific antibodies suggests the presence, in these micro-domains, of a characteristic marker of lipid rafts, the protein flotillin-1.

The NATO project: nanoparticle-based countermeasures for microgravity-induced osteoporosis.

Recent advances in nanotechnology applied to medicine and regenerative medicine have an enormous and unexploited potential for future space and terrestrial medical applications. The Nanoparticles and Osteoporosis (NATO) project aimed to develop innovative countermeasures for secondary osteoporosis affecting astronauts after prolonged periods in space microgravity. Calcium- and Strontium-containing hydroxyapatite nanoparticles (nCa-HAP and nSr-HAP, respectively) were previously developed and chemically characterized. This study constitutes the first investigation of the effect of the exogenous addition of nCa-HAP and nSr-HAP on bone remodeling in gravity (1 g), Random Positioning Machine (RPM) and onboard International Space Station (ISS) using human bone marrow mesenchymal stem cells (hBMMSCs). In 1 g conditions, nSr-HAP accelerated and improved the commitment of cells to differentiate towards osteoblasts, as shown by the augmented alkaline phosphatase (ALP) activity and the up-regulation of the expression of bone marker genes, supporting the increased extracellular bone matrix deposition and mineralization. The nSr-HAP treatment exerted a protective effect on the microgravity-induced reduction of ALP activity in RPM samples, and a promoting effect on the deposition of hydroxyapatite crystals in either ISS or 1 g samples. The results indicate the exogenous addition of nSr-HAP could be potentially used to deliver Sr to bone tissue and promote its regeneration, as component of bone substitute synthetic materials and additive for pharmaceutical preparation or food supplementary for systemic distribution.

Administration of vitamin D and high dose of omega 3 to sustain remission of type 1 diabetes.

OBJECTIVE: Two cases of Type 1 Diabetes (T1D) in pediatric subjects treated with supplementation with high dose vitamin D and omega 3 are reported. A similar pattern of remission of the disease was observed, resulting in restoration and subsequent persistence of optimal metabolic control, one and two years after T1D onset. Minimal basal insulin administration (0.1 IU/kg/die) in a single evening injection was required. The immunomodulatory and anti-inflammatory properties of the supplements were likely contributing to the observed effect. Similarities in genotyping and autoantibody patterns in these two cases could be of assistance to identify which subjects with T1D could benefit from this supplemental therapy. High dose vitamin D and omega 3 could be of assistance in childhood T1D therapy, to prolong preservation of endogenous insulin secretion in the absence of side effects. We do not know how long the state of remission can last, but these initial results are promising and represented a significant benefit for the two pediatric subjects treated. Larger controlled studies will determine the long-term effect of this proposed supplementation and its possible cost-benefits, including reduction of hypoglycemic episodes and complications.

Can Type 1 diabetes progression be halted? Possible role of high dose vitamin D and omega 3 fatty acids.

In Type 1 Diabetes (T1D) in children, close to the onset the requirements of insulin are often reduced. This represents a transient recovery of endogenous insulin secretion named "honeymoon" because transient and followed by a progressive decline in C-peptide secretion. This case report describes the effect of administration of high dose vitamin D and Ω-3 fatty acids on T1D progression in a 8-year-old child. At today after one year and a half from the onset of T1D, the subject shows a near-normal blood glucose with the administration of 1.5-2 UI of insulin once a day. Thus this report may be of assistance to design additional studies to determine and validate the effect of administration of vitamin D and Ω-3 fatty acids on the progression of T1D.

Heterogeneous and self-organizing mineralization of bone matrix promoted by hydroxyapatite nanoparticles.

The mineralization process is crucial to the load-bearing characteristics of the bone extracellular matrix. In this work, we have studied the spatiotemporal dynamics of mineral deposition by human bone marrow mesenchymal stem cells differentiating toward osteoblasts promoted by the presence of exogenous hydroxyapatite nanoparticles. At the molecular level, the added nanoparticles positively modulated the expression of bone-specific markers and enhanced calcified matrix deposition during osteogenic differentiation. The nucleation, growth and spatial arrangement of newly deposited hydroxyapatite nanocrystals have been evaluated using scanning micro X-ray diffraction and scanning micro X-ray fluorescence. As leading results, we have found the emergence of a complex scenario where the spatial organization and temporal evolution of the process exhibit heterogeneous and self-organizing dynamics. At the same time the possibility of controlling the differentiation kinetics, through the addition of synthetic nanoparticles, paves the way to empower the generation of more structured bone scaffolds in tissue engineering and to design new drugs in regenerative medicine.

Effect of maternal diet on the distribution of phospholipids and their fatty acid composition in Xenopus laevis embryos.

We determined the total phospholipid content, the percentage distribution of different phospholipid classes and their fatty acid composition in 6-day-old embryos obtained from Xenopus laevis females fed on two different diets. A first group of females was fed on beef liver, and a second one was nourished with commercial fish food very rich in omega-3 fatty acids. The embryos showed different patterns of phospholipids that had dissimilar fatty acid compositions. Phosphatidylinositol content was particularly affected. Due to the functional roles of this phospholipid as part of the transmembrane signaling machinery, it is possible to hypothesize that maternal diet might influence cell metabolism in amphibian embryos.

Exogenous sphingosine enters Xenopus laevis embryos grown in petri dishes and it is metabolized.

Xenopus embryos of different developmental stages were exposed to 0.1 microM [1-3H]sphingosine. Labeled sphingosine was quickly absorbed by Xenopus embryos. The amount of radioactivity absorbed increased with embryo age and appeared to be linearly correlated (R = 0.97) to the embryo surface area. About 45% of the total radioactivity associated to the embryos was found in the skin, 22% in the intestine, 15% in the heart, 12% in the liver and 6% in the brain. A portion of [1-3H]sphingosine entered very rapidly the biosynthetic pathway of sphingolipids; after 30 min of incubation, in fact, only a small amount of free radioactive sphingosine could be detected. Sphingomyelin was the main radioactive sphingolipid synthesized; radioactive ceramide, galactosylceramide and lactosylceramide could also be recognized and quantified. On the contrary, the amount of radioactive gangliosides was hardly detectable. A portion of [1-3H]sphinogosine absorbed by Xenopus embryos (30 to 60% depending on the developmental stage) entered the catabolic pathway producing radioactive phosphoethanolamine that was recycled for the biosynthesis of radioactive phosphatidylethanolamine. This phospholipid was produced mainly in the intestine and in the skin, while sphingomyelin was the main radioactive lipid in the heart, liver and brain.

Ocular and clinical manifestations of Möbius' syndrome.

PURPOSE: To assess ocular and otorhinolaryngologic manifestations and intellectual ability in patients with Möbius' syndrome. METHODS: Patients with Möbius' syndrome underwent prospective ophthalmic, genetic-clinical, and otorhinolaryngologic examinations as well as psychological evaluation. RESULTS: Sixteen patients with Möbius' syndrome between the ages of 8 months and 10.6 years underwent ocular examination. Esotropia was present in 12 (75%) patients and V-pattern in 8 (50%). Limited abduction was present in 30 (93.8%) eyes, and limited adduction was present in 21 (65.6%) eyes. The most frequent refractive error was compound hyperopic astigmatism (13 [40.6%] eyes). Eleven (68.8%) patients had lagophthalmos and 12 (75%) patients had bilateral epicanthus. Unilateral amblyopia was present in 2 (12.5%) patients. Clubfoot was the most common lower limb defect (7 [43.8%] patients). Cranial nerve impairments included paralysis of 7th nerve in all patients, paralysis of the 12th nerve in 13 patients, and paralysis of the 9th and 10th nerves in 3 patients. Evaluation of intellectual ability showed that 4 (25%) patients had normal intelligence. The mothers of 3 (18.8%) patients used misoprostol during the first trimester of pregnancy. CONCLUSION: Prominent ophthalmic features of Möbius' syndrome in this series were esotropia, V-pattern, abduction limitation, and compound hyperopic astigmatism. Intellectual assessment showed some degree of mental retardation in 75% of patients. Möbius' syndrome is associated with prenatal exposure to misoprostol.

[IQ in hydrocephalus and myelomeningocele. Implications of surgical treatment]. / QI em pacientes com hidrocefalia e mielomeningocele. Implicações do tratamento cirúrgico.

Myelomeningocele occurs in 0.4 for 1000 neonates and is associated with hydrocephalus in 85-90%, and reports on cognition are sparsely found in literature. Forty five children with treated hydrocephalus and myelomeningocele were studied in regard of IQ, and statistically correlated to functional motor level, age of the first shunt, number of revisions of shunt, infection of the shunt and circumference of the head. The medium age was of 7.5 years (3-15 years), 16 males and 29 females. Three (6.6%) had a IQ score > 110, 11 (24.4%) had a score between 100-110, 8 between 85-100 (17.7%), 16 (35.5%) between 85-100 (17.7%) and 7 (15.5%) between 50-70. IQ directly correlated with motor level, having better cognitive results the children with minor functional motor disabilities. Cognition was best in children operated until the seven day of life (t 0.0099), with progressive worse results in children operated after the first month of life, no significance was observed in children operated in the period 7 to 31 days (t 0.1013). Worse results were observed in the group of patients with infection of shunts (t 0.0146). Results were progressively worse with reoperations. The best results in relation of the circumference of the head were seen with children in the medium range (t 0.0115); intermediate results were seen in patients between the medium range and-1SD (t 0.00130) and medium range and +1SD. The worse results were seen in patients at the extremes of > 1SD (t 0.0269) and < ISD (t 0.0042). According to cognitive results the surgical treatment of hydrocephalus have to be done until the first month of life, avoiding reoperations and infections that have unfavorable impact in IQ.

Long chain omega 3 polyunsaturated fatty acids supplementation in the treatment of elderly depression: effects on depressive symptoms, on phospholipids fatty acids profile and on health-related quality of life.

OBJECTIVE: Recent observations showed that long chain omega 3 polyunsaturated fatty acids (n-3 LCPUFA) could represent a potential treatment for elderly depression. To determine if a n-3 LCPUFA containing supplement improves depressive symptoms, changes phospholipids acids profile and ameliorates Health related quality of life (HRQoL) in depressed elderly patients. DESIGN: Two-months, randomized, double-blind, placebo-controlled trial. SETTING: Nursing home in Pavia, Italy. SUBJECTS: Forty-six depressed females, aged 66-95 years. INTERVENTION: 22 depressed females were included in the intervention group (n-3 group, that received 2.5 g/day of n-3 LCPUFA, with 1.67 grams of EPA and 0.83 grams of DHA), and 24 patients in the placebo group. The primary endpoint was the improvement of depressive symptoms as evaluated by Geriatric Depression Scale (GDS). Secondary endpoints were the evaluation of modifications of erythrocyte membrane phospholipids fatty acid profile and of of HRQoL, by using the Short-Form 36-Item Health Survey (SF-36). All parameters were assessed before and after the treatment period of 8 weeks. RESULTS: The mean GDS at 2 months was significantly lowered only for the n-3 group. SF-36 physical and mental components were significantly increased in the intervention group. Compliance was good, as confirmed by erythrocyte membrane phospholipid FA concentrations, with significant increase of EPA and DHA in the intervention group. CONCLUSION: The supplementation of n-3 LCPUFA in elderly female patients reduces the occurrence of depressive symptoms, improves phospholipids fatty acids profile and health-related quality of life.

Blood profiles, body fat and mood state in healthy subjects on different diets supplemented with Omega-3 polyunsaturated fatty acids.

BACKGROUND: Diets and Omega-3 polyunsaturated fatty acids have been considered as important factors to reduce the risk of cardiovascular and inflammatory diseases, but there are few details on the effects on healthy subjects. The aim of the present study was to examine the variation of several physiological parameters in healthy subjects on different diets supplemented with Omega-3 fatty acids. MATERIALS AND METHODS: The experiment was carried out on 33 subjects divided into four groups according to a double-blind cross-over design with a 1 : 1 ratio for Omega-3 (vs. placebo) and open-label parallel-groups with a 1 : 1 ratio for the Zone diet (vs. the diet suggested by the Italian National Research Institute for Nutrition and Foods). Blood samples were collected at the beginning of the experiment and after 35 (cross-over) and 70 days. The Profile of Mood States test (POMS) was also performed. RESULTS: The arachidonic acid/eicosapentaenoic acid ratio (AA/EPA) was strongly reduced by Omega-3 with a supplementary effect of the diet and in particular the Zone diet. The AA/EPA reduction was correlated with a concomitant decrease of insulin and homocysteine levels. The Zone diet reduced skinfold thickness and body fat percentage and also showed antioxidant effects. The mood state changed after Omega-3 supplementation, with an increased POMS index. This was related to a concomitant reduction of AA/EPA and was particularly evident in the Zone diet. CONCLUSION: AA/EPA and mood state are differently influenced by diet and Omega-3, body fat is particularly reduced by Zone diet, while blood parameters such as triglycerides/HDL ratio, insulin and homocysteine are related to AA/EPA variations. These findings are discussed in terms of differences in the composition of the diets and the influences of Omega-3 on physiological functions.

Effect of ethanol amine plasmalogens on Fe-induced peroxidation of arachidonic acid in dipalmitoylphosphatidylcholine vesicles.

We have investigated the influence of ethanolamine plasmalogens on iron-induced oxidation of arachidonic acid in dipalmitoylphosphatidylcholine (DPPC) vesicles. Lipoperoxidation was induced by the addition of 50 microM FeSO4 and studied above (50 degrees C) and below (15 degrees C) the gel-to liquid transition temperature of the vesicles, at two different pH values (7.4 or 6.4). The extent of peroxidation was measured as thiobarbituric reactive product formed and the influence exerted by ethanolamine plasmalogens (PEPL) in this process was compared to that of dipalmitoylphosphatidylethanolamine (DPPE) and diacylphosphatidylethanolamines (DAPE). The extent of peroxidation of arachidonic acid embedded in DPPC vesicles was similar at the two temperatures and greater at 50 degrees C under acidic conditions. However, the peroxidative process was significantly decreased at 50 degrees C in the presence of PEPL, but not of DPPE or DAPE and the inhibitory effect was enhanced at pH 6.4. The possibility that a different phase distribution of the phospholipids, namely a transition from a lamellar to a hexagonal phase, may play a role in the scavenger effect of ethanolamine plasmalogens is discussed.

Cholesterol, triacylglicerols and phospholipids during Xenopus embryo development.

Cholesterol, triacylglicerol and phospholipid content was analysed in Xenopus embryos during their early development (from day 1 to day 6). Triacylglicerols decrease significantly during the analysed stages and this can be explained by their use as energy substrate. Cholesterol and phospholipids, on the contrary, remain constant and are probably redistributed inside the embryo. The different phospholipid classes were separated by HPTLC. A constant decrease of PC and a marked increase of PS has been observed. The fatty acid composition of the single phospholipid classes has been analysed.

Effect of ethanol exposure on Xenopus embryo lipid composition.

Exposure to ethanol is known to alter cell membranes both chemically and biophysically; these effects may be related to the development of tolerance and physical dependence. In the present study, the effects of various concentrations of ethanol (1-250 mM) on the lipid composition after the first 6 days of Xenopus embryo development were investigated, using an in vitro fertilization technique. Lipid analysis revealed: (1) a decrease of the cholesterol/phospholipid molar ratio mainly derived from a higher content of phospholipids; (2) an increase of phospholipid unsaturated fatty acids, especially C20:4 and C20:5, with ethanol concentration of 150-250 mM; (3) a decrease of lipid-bound sialic acid with ethanol concentrations of > or =5 mM. These results underline that sialoglycoconjugates are a more sensitive target of alcohol in comparison with other lipid components. The cultured embryo method certainly represents a useful model for investigation of the direct effects of ethanol on lipid metabolism, excluding maternal interference which can lead to misinterpretation of data.

Activities of glycolipid glycosyltransferases and sialidases during the early development of Xenopus laevis.

The activities of glycosyltransferases and sialidases, together with the ganglioside content and distribution, have been extensively studied in mammals, while the informations on tissues of other animals, including amphibian, are scarce. In this paper we present data on the activities of SAT-1, SAT-2, SAT-4, SAT-5, GlcNAcT-1, GalNAcT-1, GalT-6, and sialidases studied in Xenopus laevis embryos at different stages of development. The highest activity was found at days 4 and 5 of embryogenesis for glycosyltransferases and sialidases respectively; a tentative correlation between the in vitro activity of these enzymes and the content of neutral and acidic glycolipids is discussed.

Effects of microgravity and hypergravity on early development stages of Xeonopus laevis.

The aim of this work is to evaluate the development of X.l. in modified gravity conditions. The simulation of hyper and microgravity was performed utilizing: an hyperfuge, a Clinostat and later on a Random Positioning Machine (RPM, 3d Clinostat). The effect of hypergravity on embryos is significantly higher than that of microgravity; the exposure of embryos to 3xg for 3 days before and after hatch causes an activation of HSP-60 and HSP-70. Embryos exposed to 3xg during the first 3 days of development are very sensitive and show a retard of development, with a lower content of DNA, neutral glycolipids and gangliosides compared to controls.

Retinoic acid induces changes in Xenopus embryo glycolipid pattern.

Retinoic acid (RA), known for its important role in cellular differentiation, may cause a modification of glycolipid distribution characterized by a shift from globoserie towards latto- and ganglio-series. In the present paper, we have investigated the modifications of the lipidic pattern after exogenous RA treatment of Xenopus embryos. We have noticed a decrease in neutral glycolipids with a parallel increase in gangliosides; the content of sulfatides does not seem to be modified. Beside the shift toward ganglio-serie, we have also observed a redistribution inside this class of lipids. In particular, following RA treatment, the relative distribution of GD1b and GT1b increases while that of GM3 decreases.

Tissue and developmental specificity of a polysialo-ganglioside species in the amphibian Xenopus.

Xenopus embryos contain a considerable amount of a polysialo-ganglioside not yet fully characterized; in this paper, we will refer to it as ganglioside XI. Preliminary experiments indicate asialo-GMI as the core structure of the ganglioside XI and palmitic and oleic acid as the fatty acids of the ceramide moiety. Further analyses by comparative 2D-TLC with adult fish and chick embryo brains indicate the pentasialilated ganglioside GP1c as the possible structure of XI. In the adult Xenopus, XI characterizes the ganglioside pattern of the central nervous system while is absent in all the other tested tissues. At least two other more polar (presumably richer in sialic acid) bands are often visible under XI, both in embryos and in brain and spinal cord tissues of adult Xenopus. The persistence of polysialo-gangliosides in the brain and spinal cord of adult amphibians could serve to guarantee a proper functioning of the central nervous system at low body temperature.

Glycolipid patterns during Xenopus embryo development.

Glycolipid patterns have been studied during the first six days of Xenopus embryo development. Glycolipid contents showed a sharp increase more evident after the third day of development. Glucosylceramide and sulphatide are not only the most represented species, but also those which exhibit a statistically significant percentage change during early development. Among gangliosides, GD3 is the most represented specie. Two polysialylated gangliosides with not yet established structures are also present.