title: Gender disparity in LDL-induced cardiovascular damage and the protective role of estrogens against electronegative LDL.
abstract: BACKGROUND
  Increased levels of the most electronegative type of LDL, L5, have been observed in the plasma of patients with metabolic syndrome (MetS) and ST-segment elevation myocardial infarction and can induce endothelial dysfunction. Because men have a higher predisposition to developing coronary artery disease than do premenopausal women, we hypothesized that LDL electronegativity is increased in men and promotes endothelial damage.
  
  
  METHODS
  L5 levels were compared between middle-aged men and age-matched, premenopausal women with or without MetS. We further studied the effects of gender-influenced LDL electronegativity on aortic cellular senescence and DNA damage in leptin receptor-deficient (db/db) mice by using senescence-associated-β-galactosidase and γH2AX staining, respectively. We also studied the protective effects of 17β-estradiol and genistein against electronegative LDL-induced senescence in cultured bovine aortic endothelial cells (BAECs).
  
  
  RESULTS
  L5 levels were higher in MetS patients than in healthy subjects (P < 0.001), particularly in men (P = 0.001). LDL isolated from male db/db mice was more electronegative than that from male or female wild-type mice. In addition, LDL from male db/db mice contained abundantly more apolipoprotein CIII and induced more BAEC senescence than did female db/db or wild-type LDL. In the aortas of db/db mice but not wild-type mice, we observed cellular senescence and DNA damage, and the effect was more significant in male than in female db/db mice. Pretreatment with 17β-estradiol or genistein inhibited BAEC senescence induced by male or female db/db LDL and downregulated the expression of lectin-like oxidized LDL receptor-1 and tumor necrosis factor-alpha protein.
  
  
  CONCLUSIONS
  The gender dichotomy of LDL-induced cardiovascular damage may underlie the increased propensity to coronary artery disease in men.
authors.forename: An-Sheng
authors.initials: AS
authors.lastname: Lee
authors.forename: Wei-Yu
authors.initials: WY
authors.lastname: Chen
authors.forename: Hua-Chen
authors.initials: HC
authors.lastname: Chan
authors.forename: Jing-Fang
authors.initials: JF
authors.lastname: Hsu
authors.forename: Ming-Yi
authors.initials: MY
authors.lastname: Shen
authors.forename: Chia-Ming
authors.initials: CM
authors.lastname: Chang
authors.forename: Henry
authors.initials: H
authors.lastname: Bair
authors.forename: Ming-Jai
authors.initials: MJ
authors.lastname: Su
authors.affiliation: Division of Cardiology, China Medical University Hospital, Taichung City, Taiwan. kuancheng.chang@gmail.com.
authors.forename: Kuan-Cheng
authors.initials: KC
authors.lastname: Chang
authors.forename: Chu-Huang
authors.initials: CH
authors.lastname: Chen
mesh_terms: D000818:Animals; D001011:Aorta / Q000187:drug effects* / Q000473:pathology*; D002318:Cardiovascular Diseases / Q000473:pathology / Q000517:prevention & control; D002417:Cattle; D002478:Cells, Cultured; D004249:DNA Damage / Q000187:drug effects / Q000502:physiology; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008077:Lipoproteins, LDL / Q000096:biosynthesis / Q000633:toxicity*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008875:Middle Aged; D009924:Organ Culture Techniques; D012727:Sex Characteristics
chemical_list: D004967:Estrogens; D008077:Lipoproteins, LDL