title: Eryptosis in lead-exposed workers.
abstract: Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8μg/dl) and non-exposed workers (4.2μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca(2+)]i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (<0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca(2+)], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications.
authors.affiliation: Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF, Mexico.
authors.forename: Itzel-Citlalli
authors.initials: IC
authors.lastname: Aguilar-Dorado
authors.affiliation: Section of Methodology of Science, Centro de Investigación y Estudios Avanzados IPN, México, DF, Mexico.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Hernández
authors.affiliation: Faculty of Medicine, UJED, Durango, DGO, Mexico.
authors.forename: Martha-Angelica
authors.initials: MA
authors.lastname: Quintanar-Escorza
authors.affiliation: CIATEC, León, GTO, Mexico.
authors.forename: María
authors.initials: M
authors.lastname: Maldonado-Vega
authors.affiliation: Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF, Mexico.
authors.forename: Margarita
authors.initials: M
authors.lastname: Rosas-Flores
authors.affiliation: Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF, Mexico. Electronic address: jcalder@cinvestav.mx.
authors.forename: José-Víctor
authors.initials: JV
authors.lastname: Calderón-Salinas
mesh_terms: D000255:Adenosine Triphosphate / Q000097:blood; D000328:Adult; D015415:Biomarkers / Q000097:blood; D002118:Calcium / Q000097:blood; D002154:Calpain / Q000097:blood; D016022:Case-Control Studies; D011211:Electric Power Supplies / Q000009:adverse effects*; D004913:Erythrocytes, Abnormal / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D005978:Glutathione / Q000097:blood; D006801:Humans; D007854:Lead / Q000009:adverse effects*; D007855:Lead Poisoning / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000097:blood / Q000139:chemically induced* / Q000175:diagnosis; D016273:Occupational Exposure / Q000009:adverse effects*; D016272:Occupational Health; D018384:Oxidative Stress / Q000187:drug effects; D010718:Phosphatidylserines / Q000097:blood; D000623:Porphobilinogen Synthase / Q000097:blood; D059027:Recycling; D018570:Risk Assessment; D012307:Risk Factors; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D055815:Young Adult
chemical_list: D015415:Biomarkers; D010718:Phosphatidylserines; D017392:Thiobarbituric Acid Reactive Substances; D007854:Lead; D000255:Adenosine Triphosphate; D002154:Calpain; C449002:mu-calpain; D000623:Porphobilinogen Synthase; D005978:Glutathione; D002118:Calcium
keywords: Human erythrocytes; Intracellular free calcium; Lead intoxication; Oxidative damage; μ-Calpain