title: The role of dyslipidemia on ocular surface, lacrimal and meibomian gland structure and function.
abstract: OBJECTIVE
  Dyslipidemia is characterized by high lipid blood levels that are risk factors for cardiovascular diseases, which are leading causes of death. However, it is unclear whether dyslipidemia is a cause of the dry eye syndrome (DES). Therefore we determined in transgenic mice models of dyslipidemia, whether there is an association with DES development.
  
  
  METHODS
  Dyslipidemic models included male and female adult mice overexpressing apolipoprotein CIII (Apo CIII), LDL receptor knockout (LDLR-KO) and ApoE knockout (ApoE-KO). They were compared with age- and gender-matched C57BL/6 mice. Ocular health was evaluated based on corneal slit lamp assessment, phenol red thread test (PRT) and impression cytology. Blood lipid profiles and histology of meibomian and lacrimal glands were also evaluated. Effects of high-fat diet and aging were observed in LDLR-KO and ApoCIII strains, respectively.
  
  
  RESULTS
  Body weight and lacrimal gland weight were significantly higher in male mice compared to females of the same strain (P < 0.05). Body weight was significantly lower in LDLRKO mice receiving high lipid diet compared to their controls (P = 0.0043). ApoE-KO were hypercholesterolemic and ApoCIII hypertriglyceridemic while LDLR-KO showed increases in both parameters. The PRT test was lower in male LDLR-KO mice with high-fat diet than control mice with standard diet (P = 0.0273). Aging did not affect lacrimal structural or functional parameters of ApoCIII strain.
  
  
  CONCLUSIONS
  DES development is not solely dependent on dyslipidemia in relevant mice models promoting this condition. On the other hand, lacrimal gland structure and function are differentially impacted by lipid profile changes in male and female mice. This dissociation suggests that other factors beside dyslipidemia impact on tear film dysfunction and DES development.
authors.affiliation: Department of Ophthalmology, Faculty of Medicine of Ribeirão Preto, USP, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Carolina Maria
authors.initials: CM
authors.lastname: Módulo
authors.forename: Elísio Bueno
authors.initials: EB
authors.lastname: Machado Filho
authors.forename: Leonardo Tannus
authors.initials: LT
authors.lastname: Malki
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: Dias
authors.forename: Jane Cristina
authors.initials: JC
authors.lastname: de Souza
authors.forename: Helena C F
authors.initials: HC
authors.lastname: Oliveira
authors.forename: Italo Cade
authors.initials: IC
authors.lastname: Jorge
authors.forename: Isabele Beserra
authors.initials: IB
authors.lastname: Santos Gomes
authors.forename: Silvana S
authors.initials: SS
authors.lastname: Meyrelles
authors.forename: Eduardo Melani
authors.initials: EM
authors.lastname: Rocha
mesh_terms: D000818:Animals; D003315:Cornea / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D015352:Dry Eye Syndromes / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D050171:Dyslipidemias / Q000150:complications / Q000378:metabolism*; D005260:Female; D005500:Follow-Up Studies; D007765:Lacrimal Apparatus / Q000378:metabolism / Q000473:pathology*; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008297:Male; D008537:Meibomian Glands / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D012307:Risk Factors; D013666:Tears / Q000737:chemistry*
chemical_list: D008077:Lipoproteins, LDL