title: Relationship between Carotenoids, Retinol, and Estradiol Levels in Older Women.
abstract: BACKGROUND
  In vitro evidence suggests anti-estrogenic properties for retinol and carotenoids, supporting a chemo-preventive role of these phytochemicals in estrogen-dependent cancers. During aging there are significant reductions in retinol and carotenoid concentrations, whereas estradiol levels decline during menopause and progressively increase from the age of 65. We aimed to investigate the hypothesis of a potential relationship between circulating levels of retinol, carotenoids, and estradiol (E2) in a cohort of late post-menopausal women.
  
  
  METHODS
  We examined 512 women ≥ 65 years from the InCHIANTI study. Retinol, α-caroten, β-caroten, β-criptoxantin, lutein, zeaxanthin, and lycopene levels were assayed at enrollment (1998-2000) by High-Performance Liquid Chromatography. Estradiol and testosterone (T) levels were assessed by Radioimmunometry (RIA) and testosterone-to-estradiol ratio (T/E2), as a proxy of aromatase activity, was also calculated. General linear models adjusted for age (Model 1) and further adjusted for other confounders including Body Mass Index (BMI) BMI, smoking, intake of energy, lipids, and vitamin A; C-Reactive Protein, insulin, total cholesterol, liver function, and testosterone (Model 2) were used to investigate the relationship between retinol, carotenoids, and E2 levels. To address the independent relationship between carotenoids and E2 levels, factors significantly associated with E2 in Model 2 were also included in a fully adjusted Model 3.
  
  
  RESULTS
  After adjustment for age, α-carotene (β ± SE = -0.01 ± 0.004, p = 0.02) and β-carotene (β ± SE = -0.07 ± 0.02, p = 0.0007) were significantly and inversely associated with E2 levels. α-Carotene was also significantly and positively associated with T/E2 ratio (β ± SE = 0.07 ± 0.03, p = 0.01). After adjustment for other confounders (Model 2), the inverse relationship between α-carotene (β ± SE = -1.59 ± 0.61, p = 0.01), β-carotene (β ± SE = -0.29 ± 0.08, p = 0.0009), and E2 persisted whereas the relationship between α-carotene and T/E2 ratio was attenuated (β ± SE = 0.22 ± 0.12, p = 0.07). In a fully adjusted model (Model 3), only β-carotene (β ± SE = -0.05 ± 0.02, p = 0.03) was significantly and inversely associated with E2 levels independent of α-carotene. No association was found between retinol, total non-pro-vitamin A carotenoids, lutein, zeaxanthin, and lycopene, and E2 levels.
  
  
  CONCLUSIONS
  In older women, β-carotene levels are independently and inversely associated with E2.
authors.affiliation: Department of Clinical and Experimental Medicine, University of Parma, Via Gramsci 14, Parma 43126, Italy. flauretani@ao.pr.it.|Geriatric Rehabilitation Department, University Hospital of Parma, Via Gramsci 14, Parma 43126, Italy. flauretani@ao.pr.it.
authors.forename: Marcello
authors.initials: M
authors.lastname: Maggio
authors.affiliation: Department of Clinical and Experimental Medicine, University of Parma, Via Gramsci 14, Parma 43126, Italy. francy_devita@hotmail.it.
authors.forename: Francesca
authors.initials: F
authors.lastname: de Vita
authors.affiliation: Geriatric Rehabilitation Department, University Hospital of Parma, Via Gramsci 14, Parma 43126, Italy. flauretani@ao.pr.it.
authors.forename: Fulvio
authors.initials: F
authors.lastname: Lauretani
authors.affiliation: Geriatric Unit, Azienda Sanitaria di Firenze, Florence 50100, Italy. stefania.bandinelli@asf.toscana.it.
authors.forename: Stefania
authors.initials: S
authors.lastname: Bandinelli
authors.affiliation: Department of Ophthalmology, Johns Hopkins University School of Medicine, 733 North Broadway Baltimore, MD 21225, USA. rdsemba@jhmi.edu.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Semba
authors.affiliation: New England Research Institute, 480 Pleasant Street, Watertown, MA 02472, USA. bbartali@neriscience.com.
authors.forename: Benedetta
authors.initials: B
authors.lastname: Bartali
authors.affiliation: Geriatrics, IRCCS-INRCA, Via della Montagnola, Ancona 81 60127, Italy. A.CHERUBINI@inrca.it.
authors.forename: Antonio
authors.initials: A
authors.lastname: Cherubini
authors.affiliation: Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Perelman School of Medicine at the University of Pennsylvania, 295 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA 19104, USA. acappola@mail.med.upenn.edu.
authors.forename: Anne R
authors.initials: AR
authors.lastname: Cappola
authors.affiliation: Department of Clinical and Experimental Medicine, University of Parma, Via Gramsci 14, Parma 43126, Italy. flauretani@ao.pr.it.|Geriatric Rehabilitation Department, University Hospital of Parma, Via Gramsci 14, Parma 43126, Italy. flauretani@ao.pr.it.
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Ceda
authors.affiliation: National Institute on Aging, National Institutes of Health (NIH), Harbor Hospital 3001 Hanover Street Baltimore, MD 21225, USA. ferruccilu@grc.nia.nih.gov.
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D002338:Carotenoids / Q000097:blood*; D002784:Cholesterol / Q000097:blood; D003430:Cross-Sectional Studies; D004958:Estradiol / Q000097:blood*; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D014975:Lutein / Q000097:blood; D000077276:Lycopene; D008875:Middle Aged; D013739:Testosterone / Q000097:blood; D014801:Vitamin A / Q000097:blood*; D055815:Young Adult; D065146:Zeaxanthins / Q000097:blood; D019207:beta Carotene / Q000097:blood*
chemical_list: D007328:Insulin; D065146:Zeaxanthins; D019207:beta Carotene; D014801:Vitamin A; D002338:Carotenoids; D013739:Testosterone; C041635:alpha-carotene; D004958:Estradiol; D002097:C-Reactive Protein; D002784:Cholesterol; D000077276:Lycopene; D014975:Lutein
keywords: carotenoids; elderly; estrogens; retinol; women