title: Structural changes in dermal collagen and oxidative stress levels in the skin of Japanese overweight males.
abstract: OBJECTIVE
  It has been reported that obese people have poorly organized dermal collagen structure because of the degradation of collagen fibers, which is caused by an increase in oxidative stress levels associated with the hypertrophy of subcutaneous adipose cells. However, it is unclear whether an increase in oxidative stress levels caused by the accumulation of subcutaneous adipose tissue and a change in the dermal structure also occur in overweight and obese Japanese people. The objectives of this study are to identify structural changes that occur in the dermis and to measure the levels of oxidative stress in Japanese overweight males.
  
  
  METHODS
  The overweight group included 43 Japanese male volunteers aged between 25 and 64 years and with a body mass index (BMI) of ≥25 and <30. The control group included 47 male volunteers aged between 22 and 64 years and with BMI of <25. The 20-MHz Dermascan C® ultrasound scanner with software for image analyses was used. Echogenicity of the upper and lower dermis was measured. The mRNA expression level of heme oxygenase-1 (HMOX1) in hair follicles was quantitatively analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) and was used as a marker of oxidative stress. Ultrasonographic imaging and collection of hair follicles were performed at the same site on the thigh, abdomen, and upper arm.
  
  
  RESULTS
  The HMOX1 mRNA expression level in the abdomen and thigh was significantly lower in the overweight group than in the control group. Moreover, the echogenicity of the upper dermis of the abdomen and the lower dermis of the abdomen and thigh was significantly lower in the overweight group than in the control group.
  
  
  CONCLUSIONS
  We detected an increase in oxidative stress levels and a decrease in the density of dermal collagen at the same site on the thigh, abdomen, and upper arm of Japanese overweight males. These findings suggest the fragility of the dermis of Japanese overweight males, which might have been caused by the accumulation of subcutaneous adipose tissue.
authors.affiliation: Department of Clinical Nursing, Division of Health Science, Graduate School of Medicine, Kanazawa University, Ishikawa, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Matsumoto
authors.forename: A
authors.initials: A
authors.lastname: Ibuki
authors.forename: T
authors.initials: T
authors.lastname: Minematsu
authors.forename: J
authors.initials: J
authors.lastname: Sugama
authors.forename: M
authors.initials: M
authors.lastname: Horii
authors.forename: K
authors.initials: K
authors.lastname: Ogai
authors.forename: T
authors.initials: T
authors.lastname: Nishizawa
authors.forename: M
authors.initials: M
authors.lastname: Dai
authors.forename: A
authors.initials: A
authors.lastname: Sato
authors.forename: Y
authors.initials: Y
authors.lastname: Fujimoto
authors.forename: M
authors.initials: M
authors.lastname: Okuwa
authors.forename: G
authors.initials: G
authors.lastname: Nakagami
authors.forename: T
authors.initials: T
authors.lastname: Nakatani
authors.forename: H
authors.initials: H
authors.lastname: Sanada
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003094:Collagen / Q000737:chemistry / Q000378:metabolism*; D003430:Cross-Sectional Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000378:metabolism*; D018384:Oxidative Stress; D011487:Protein Conformation; D012867:Skin / Q000378:metabolism*
chemical_list: D003094:Collagen
keywords: Japanese overweight males; dermal collagen; echogenicity; oxidative stress; real-time RT-PCR; skin fragility; ultrasonographic imaging