title: Early postnatal lead exposure induces tau phosphorylation in the brain of young rats.
abstract: Cognitive impairment is a common feature of both lead exposure and hyperphosphorylation of tau. We, therefore, investigated whether lead exposure would induce tau hyperphosphorylation. Wistar rat pups were exposed to 0.2% lead acetate via their dams' drinking water from postnatal day 1 to 21. Lead in blood and brain were measured by atomic absorption spectrophotometry and the expression of tau, phosphorylated tau and various serine/threonine protein phosphatases (PP1, PP2A, PP2B and PP5) in the brain was analyzed by Western blot. Lead exposure significantly impaired learning and resulted in a significant reduction in the expression of tau but increased the phosphorylation of tau at Ser199/202, Thr212/Ser214 and Thr231. PP2A expression decreased, whereas, PP1 and PP5 expression increased in lead-exposed rats. These results demonstrate that early postnatal exposure to lead decrease PP2A expression and induce tau hyperphosphorylation at several serine and threonine residues. Hyperphosphorylation of tau may be a mechanism of Pb-induced deficits in learning and memory.
authors.affiliation: Department of Family Sciences, College for Women, Kuwait University, Kuwait. abdurrahman.ahmad@ku.edu.kw
authors.forename: A
authors.initials: A
authors.lastname: Rahman
authors.forename: K M
authors.initials: KM
authors.lastname: Khan
authors.forename: G
authors.initials: G
authors.lastname: Al-Khaledi
authors.forename: I
authors.initials: I
authors.lastname: Khan
authors.forename: Sreeja
authors.initials: S
authors.lastname: Attur
mesh_terms: D000367:Age Factors; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D015153:Blotting, Western; D001921:Brain / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D003071:Cognition / Q000187:drug effects; D020263:Lead Poisoning, Nervous System / Q000209:etiology* / Q000378:metabolism / Q000523:psychology; D007858:Learning / Q000187:drug effects; D008568:Memory / Q000187:drug effects; D009687:Nuclear Proteins / Q000378:metabolism; D009942:Organometallic Compounds / Q000097:blood / Q000633:toxicity*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism; D010766:Phosphorylation; D054645:Protein Phosphatase 1 / Q000378:metabolism; D054648:Protein Phosphatase 2 / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013054:Spectrophotometry, Atomic; D013997:Time Factors; D015854:Up-Regulation; D014874:Water Pollutants, Chemical / Q000009:adverse effects* / Q000097:blood; D016875:tau Proteins / Q000378:metabolism*
chemical_list: C489131:Mapt protein, rat; D009687:Nuclear Proteins; D009942:Organometallic Compounds; D014874:Water Pollutants, Chemical; D016875:tau Proteins; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D054648:Protein Phosphatase 2; C089641:protein phosphatase 5; C008261:lead acetate