title: Protein oxidation seems to be linked to constitutive autophagy: a sex study.
abstract: OBJECTIVE
  Although constitutive autophagy is linked to redox state and participates in cell homeostasis, it is scarcely known if redox state, autophagy, and lysosomal function depend on sex, a factor that largely influences health and diseases. Therefore, we evaluated the existence of sex differences in redox state and constitutive autophagy in rat tissues.
  
  
  METHODS
  7week old Sprague-Dawley rats were used to obtain organs. Malondialdehyde (MDA), and carbonylated proteins were measured by spectrophotometric methods for redox state assessment. The autophagy biomarkers Beclin-1, and microtubule-associated protein 1 light chain 3 (LC3), the mammalian target of rapamycin (mTOR; checkpoint in autophagic process), and the lysosomal associated membrane protein (LAMP-1; biomarker of lysosomes) were evaluated by Western blotting. Immunofluorescence analysis was also performed for LC3 and LAMP-1 colocalization.
  
  
  RESULTS
  In the heart, Beclin-1, and LC3-II/LC3-I were higher in males than in females suggesting that the male heart has a major constitutive autophagy and this was linked with higher levels of carbonyl groups, indicating that protein oxidation could play a role. In the liver, it was found that LAMP-1 was higher in males and greatly colocalized with LC3 indicating a larger number of autophagolysosomes. None of the above parameters was significantly different in the kidneys of both sexes with the exception of MDA, which was significantly higher in females.
  
  
  CONCLUSIONS
  The above results suggest that sex differences exist in redox state and autophagy and they occur in an organ-specific way. Importantly, it seems that the protein oxidation is more linked with constitutive autophagy, at least in cardiac ventricles, in comparison with lipid peroxidation.
authors.affiliation: Department of Biomedical Sciences, University of Sassari, Via Muroni 23, Sassari, Italy. icampesi@uniss.it
authors.forename: Ilaria
authors.initials: I
authors.lastname: Campesi
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Straface
authors.forename: Stefano
authors.initials: S
authors.lastname: Occhioni
authors.forename: Andrea
authors.initials: A
authors.lastname: Montella
authors.forename: Flavia
authors.initials: F
authors.lastname: Franconi
mesh_terms: D000818:Animals; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D001343:Autophagy / Q000502:physiology*; D000071186:Beclin-1; D005260:Female; D051907:Lysosomal Membrane Proteins / Q000378:metabolism; D008247:Lysosomes / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D010084:Oxidation-Reduction; D010588:Phagosomes / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012727:Sex Characteristics; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism; D052118:Lysosomal-Associated Membrane Protein 1
chemical_list: D051017:Apoptosis Regulatory Proteins; D000071186:Beclin-1; D051907:Lysosomal Membrane Proteins; D008315:Malondialdehyde; D008869:Microtubule-Associated Proteins; D058570:TOR Serine-Threonine Kinases; C512829:Becn1 protein, rat; C526109:Anxa3 protein, rat; C489117:Lamp1 protein, rat; D052118:Lysosomal-Associated Membrane Protein 1; C546845:mTOR protein, rat
keywords: Autophagy; Lysosomes; Protein carbonylation; Sex