title: Effect of apolipoprotein E (APO E) polymorphism on leptin in Alzheimer's disease.
abstract: BACKGROUND
  Leptin, a 16 kDa peptide hormone synthesized and secreted specifically from white adipose cells protects neurons against amyloid β-induced toxicity, by increasing Apolipoprotein E (APO E)-dependent uptake of β amyloid into the cells, thereby, protect individuals from developing Alzheimer's disease (AD). The APO E ε4 allele is a known genetic risk factor for AD by accelerating onset. It is estimated that the lifetime risk of developing AD increases to 29% for carriers with one ε4 allele and 9% for those with no ε4 allele.
  
  
  OBJECTIVE
  To determine the levels of serum leptin, cholesterol, low density lipoprotein (LDL-C), and high density lipoprotein (HDL-C) in the diagnosed cases of AD and the association of them with cognitive decline and Apolipoprotein E (APO E) genotypes in AD.
  
  
  METHODS
  Serum levels of serum leptin, cholesterol, LDL-C, and HDL-C along with APO E polymorphism were studied in 39 subjects with probable AD and 42 cognitive normal individuals.
  
  
  RESULTS
  AD group showed significantly lower levels of leptin (P = 0.00) as compared to control group. However, there was no significant difference in cholesterol, triglycerides, LDL-C, and HDL-C levels in AD and control groups. The frequency of ε4 allele in AD (38.5%) was found to be significantly higher than in control (10.3%). ε3 allele was more frequent than ε4 allele in AD and control group.
authors.affiliation: Department of Neurochemistry, Institute of Human Behaviour and Allied Sciences, Delhi, India.
authors.forename: Rachna
authors.initials: R
authors.lastname: Agarwal
authors.affiliation: Genetics and Molecular Medicine, Institute of Genomics and Integrated Biology, Delhi, India.
authors.forename: Puneet
authors.initials: P
authors.lastname: Talwar
authors.affiliation: Department of Neurology, Institute of Human Behaviour and Allied Sciences, Delhi, India.
authors.forename: Suman S
authors.initials: SS
authors.lastname: Kushwaha
authors.affiliation: Department of Biostatistics, Institute of Human Behaviour and Allied Sciences, Delhi, India.
authors.forename: Chandra Bhushan
authors.initials: CB
authors.lastname: Tripathi
authors.affiliation: Genetics and Molecular Medicine, Institute of Genomics and Integrated Biology, Delhi, India.
authors.forename: Ritushree
authors.initials: R
authors.lastname: Kukreti
keywords: APO E polymorphism; Alzheimer's disease; dementia; leptin; total cholesterol