title: Protective effects of Aloe sterols against UVB-induced photoaging in hairless mice.
abstract: BACKGROUND
  Aloe vera is a traditional medical plant whose gel has been widely used in skin care. Previously, we have identified Aloe sterols from Aloe vera as active ingredients. This study investigated the protective effects of Aloe sterols without polysaccharides, against ultraviolet B (UVB)-induced skin photoaging in mice using Aloe vera gel extract (AVGE) obtained by supercritical fluid extraction.
  
  
  METHODS
  Aloe vera gel extract was supplemented in the diet (12 or 120 ppm), and HR-1 hairless mice were exposed to UVB irradiation for 7 weeks. Skin measurements and histological and analytical studies were performed.
  
  
  RESULTS
  Repeated UVB irradiation induced rough wrinkling of skin with water content reduction and hyperkeratosis. AVGE administration resulted in the significant improvement of UVB-induced skin dryness, epidermal thickness, and wrinkle formation. The AVGE group also suppressed the degenerations of dermal collagen fibers and the appearance of cutaneous apoptosis cells induced by UVB. Furthermore, AVGE administration reduced the excess elevation of pro-inflammatory cytokines (IL-1β and TNF-α) and matrix metalloproteinases (MMP-2, MMP-9, MMP-12, and MMP-13) in UVB-exposed skin.
  
  
  CONCLUSIONS
  The dietary ingestion of Aloe sterols protected against chronic UVB damage in mouse skin, and our results suggest that Aloe sterols may prevent skin photoaging through the anti-inflammation and MMP regulation.
authors.affiliation: Food Science & Technology Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan.
authors.forename: Eriko
authors.initials: E
authors.lastname: Misawa
authors.affiliation: Food Science & Technology Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Food Science & Technology Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan.
authors.forename: Marie
authors.initials: M
authors.lastname: Saito
authors.affiliation: Food Science & Technology Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan.
authors.forename: Kazumi
authors.initials: K
authors.lastname: Nabeshima
authors.affiliation: Food Science & Technology Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan.
authors.forename: Ruiqing
authors.initials: R
authors.lastname: Yao
authors.affiliation: Food Science & Technology Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan.
authors.forename: Kouji
authors.initials: K
authors.lastname: Yamauchi
authors.affiliation: Food Science & Technology Institute, Morinaga Milk Industry Co., Ltd., Kanagawa, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Abe
authors.affiliation: Department of Dermatology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Department of Dermatology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Fukumi
authors.initials: F
authors.lastname: Furukawa
mesh_terms: D000504:Aloe; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D003094:Collagen / Q000378:metabolism; D004817:Epidermis / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D005260:Female; D005782:Gels; D053583:Interleukin-1beta / Q000378:metabolism; D020782:Matrix Metalloproteinases / Q000378:metabolism; D051379:Mice; D008812:Mice, Hairless; D010936:Plant Extracts / Q000494:pharmacology*; D020011:Protective Agents / Q000494:pharmacology; D015595:Skin Aging / Q000187:drug effects* / Q000473:pathology / Q000528:radiation effects; D013261:Sterols / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014870:Water Loss, Insensible
chemical_list: D005782:Gels; D053583:Interleukin-1beta; D010936:Plant Extracts; D020011:Protective Agents; D013261:Sterols; D014409:Tumor Necrosis Factor-alpha; D003094:Collagen; D020782:Matrix Metalloproteinases
keywords: 
  UV
  ; Aloe vera gel; photoaging; plant sterols