A5102958333- Peroxisome Proliferator-Activated Receptors
- Ethics and bioethics in healthcare
- Adenosine and Purinergic Signaling
- Adipose Tissue and Metabolism
- Drug Transport and Resistance Mechanisms
- Bone and Joint Diseases
- Pluripotent Stem Cells Research
- Cholesterol and Lipid Metabolism
- Biomedical Ethics and Regulation
- Metabolism and Genetic Disorders
- Metabolism, Diabetes, and Cancer
- Carcinogens and Genotoxicity Assessment
- Nuclear Receptors and Signaling
- Ethics in medical practice
- Birth, Development, and Health
- DNA Repair Mechanisms
- Aquaculture Nutrition and Growth
- Gout, Hyperuricemia, Uric Acid
- Renal and related cancers
- Liver Disease Diagnosis and Treatment
- Mitochondrial Function and Pathology
- Immune Cell Function and Interaction
- Psychology Research and Bibliometrics
- Cellular transport and secretion
- Machine Learning in Bioinformatics
Finis Terrae University
2023
Pontificia Universidad Católica de Chile
2008-2017
Sociedad de Biología de Chile
2006-2010
University of Chile
2000
Icahn School of Medicine at Mount Sinai
1992-2000
Rockefeller University
1987-1989
Universidad Complutense de Madrid
1985
An entire organelle, the peroxisome, appears to be missing in Zellweger syndrome, causing profound neurological problems and neonatal death. One hypothesis for molecular cause of this defect is a failure assembly peroxisomal membrane. alternative that membrane assembled, but post-translational import matrix proteins defective. We have investigated these possibilities by analytical cell fractionation, immunoblotting, immunoelectron microscopy fibroblasts. identified four integral can serve as...
The cellular mechanism of cholesterol transport from the endoplasmic reticulum to plasma membrane is currently unknown. To assess possibility that sterol carrier protein-2 (SCP-2) involved in this transport, we studied time course newly synthesized incorporation normal and SCP-2-deficient (Zellweger syndrome) human fibroblasts.Cholesterol transfer was rapid, cytoskeleton-independent, Golgi-independent cells, but it slower, cytoskeleton-dependent, Golgi-dependent cells. After SCP-2 antisense...
Alzheimer disease is a neurodegenerative process that leads to severe cognitive impairment as consequence of selective death neuronal populations. The molecular pathogenesis involves the participation β-amyloid peptide (Aβ) and oxidative stress. We report here peroxisomal proliferation attenuated Aβ-dependent toxicity in hippocampal neurons. Pretreatment with Wy-14.463 (Wy), peroxisome proliferator, prevent cell neuritic network loss induced by Aβ peptide. Moreover, neurons treated this...
Recent studies showed that the activation of retinoid X receptor, which dimerizes with peroxisome proliferator-activated receptors (PPARs), leads to an enhanced clearance Aβ from brain transgenic mice model Alzheimer's disease (AD), because increased expression apolipoprotein E and it main transporters. However, effects observed must involve additional underlying mechanisms have not been yet explored. Several conducted in our laboratory suggest part for PPARs agonist might involves...
We have previously reported the isolation of Chinese hamster ovary (CHO) cell mutants that are defective in biosynthesis plasmalogens, deficient at least two peroxisomal enzymes (dihydroxyacetonephosphate (DHAP) acyltransferase and alkyl-DHAP synthase), which catalase is not found within peroxisomes (Zoeller, R. A., Raetz, C. H. (1986) Proc. Natl. Acad. Sci. U.S.A. 83, 5170). now provide further evidence three such strains more generally peroxisome biogenesis. Electron microscopic...
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive deterioration of cognitive abilities, accumulation the amyloid-β peptide (Aβ), increase oxidative stress, and synaptic alterations. The scavenging reacti
Biliary cholesterol represents one of the two major excretory pathways for sterol elimination from body and plays a central role in gallstone formation. originates precursor pool preformed newly synthesized free cholesterol. Although it has been suggested that biliary are secreted by independent pathways, specific cellular molecular mechanisms unknown. We used male Wistar rats to study time-course appearance cholesterol, phosphatidylcholine protein into bile. The carrier protein-2 (SCP-2)...
Abstract The mechanisms of peroxisomal biogenesis remain incompletely understood, specially regarding the role endoplasmic reticulum (ER) in human cells, where genetic disorders peroxisome lead to Zellweger syndrome (ZS). Pex3p membrane protein (PMP) required for early steps has been detected ER yeast but not mammalian cells. Here, we show that Pex3p‐GFP expressed a new ZS cell line (MR), which lacks peroxisomes due mutation PEX3 gene, localizes first and subsequently newly formed...
Abstract Empty membrane ghosts of peroxisomes were found in fibroblasts from a patient with Zellweger's syndrome, genetic disease humans (Santos et al: Science 239:1536–1538, 1988). Import soluble matrix proteins into the organelle was defective. We have now studied seven patients representing five complementation groups syndrome (defined by for peroxisome enzyme function). find that empty are present all cell samples. Three patients, three groups, give same pattern immunofluorescence: few...
Feeding a 0.5% diosgenin plus 0.02% simvastatin diet to rats increases biliary cholesterol concentration and saturation levels generally found in human native supersaturated bile. By using preparative ultracentrifugation, gel filtration chromatography, electron microscopy, we isolated, purified, identified lamellar structures (unilamellar vesicles multilamellae) as major transport rat It was estimated that more than 60% of is transported these carriers, which were by transmission microscopy...
Summary— Peroxisome ghosts are aberrant peroxisomal structures found in cultured skin fibroblasts from patients affected by Zellweger Syndrome (ZS), a genetic disorder of assembly. They contain integral membrane proteins (PxIMPs) and they lack most the matrix enzymes that should be inside organelle (Santos et al., Science 239 (1988) 1536–1538). Considerable evidence indicates these result defects cellular machinery for importing newly‐synthesized into organelle. In contrast to observations,...
The issue of when the human life begins is a very important subject since it has signifi cant impact on decisions that we have to take in relation beings development, particularly embryos.In this article discuss some more relevant biological evidence supporting fact beginning unquestionably at fertilization and bioethical consequences.
Peroxisomes are thought to be formed by division of pre-existing peroxisomes after the import newly synthesized proteins.However, it has been recently suggested that endoplasmic reticulum (ER) provides an alternative de novo mechanism for peroxisome biogenesis in some cells.To test a possible role ER-Golgi transit mammalian cells, we evaluated three peroxisomal membrane proteins (PMPs): ALDRP (adrenoleukodystrophy related protein), PMP70 and Pex3p CHO cells.We constructed chimeric genes...
In ataxia telangiectasia (A-T), the lack of a functional ATM kinase is associated with disturbances in processing DNA damage and chronic oxidative stress. These may be responsible for an increment chromosomal A-T cells.To study vitro effect vitamin E (DL-alpha-tocopherol) on frequency lymphocytes from patients A-T.Seven age-sex matched controls were studied. Chromosomal mitosis was evaluated cultures both under basal conditions when G2 repair prevented by 5 mM caffeine.In cells A-T, induced...