title: Preventive effects of Chlorella on skeletal muscle atrophy in muscle-specific mitochondrial aldehyde dehydrogenase 2 activity-deficient mice.
abstract: BACKGROUND
  Oxidative stress is involved in age-related muscle atrophy, such as sarcopenia. Since Chlorella, a unicellular green alga, contains various antioxidant substances, we used a mouse model of enhanced oxidative stress to investigate whether Chlorella could prevent muscle atrophy.
  
  
  METHODS
  Aldehyde dehydrogenase 2 (ALDH2) is an anti-oxidative enzyme that detoxifies reactive aldehydes derived from lipid peroxides such as 4-hydroxy-2-nonenal (4-HNE). We therefore used transgenic mice expressing a dominant-negative form of ALDH2 (ALDH2*2 Tg mice) to selectively decrease ALDH2 activity in the muscles. To evaluate the effect of Chlorella, the mice were fed a Chlorella-supplemented diet (CSD) for 6 months.
  
  
  RESULTS
  ALDH2*2 Tg mice exhibited small body size, muscle atrophy, decreased fat content, osteopenia, and kyphosis, accompanied by increased muscular 4-HNE levels. The CSD helped in recovery of body weight, enhanced oxidative stress, and increased levels of a muscle impairment marker, creatine phosphokinase (CPK) induced by ALDH2*2. Furthermore, histological and histochemical analyses revealed that the consumption of the CSD improved skeletal muscle atrophy and the activity of the mitochondrial cytochrome c oxidase.
  
  
  CONCLUSIONS
  This study suggests that long-term consumption of Chlorella has the potential to prevent age-related muscle atrophy.
authors.affiliation: Department of Research and Development, Chlorella Industry Co, Ltd, 1343 Hisatomi, Chikugo, Fukuoka 833-0056, Japan. yuya_nakashima@chlorella.co.jp.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Nakashima
authors.forename: Ikuroh
authors.initials: I
authors.lastname: Ohsawa
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Nishimaki
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Kumamoto
authors.forename: Isao
authors.initials: I
authors.lastname: Maruyama
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Shigeo
authors.initials: S
authors.lastname: Ohta
mesh_terms: D000444:Aldehyde Dehydrogenase / Q000172:deficiency* / Q000235:genetics; D000071396:Aldehyde Dehydrogenase, Mitochondrial; D000818:Animals; D002708:Chlorella / Q000737:chemistry* / Q000378:metabolism*; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008928:Mitochondria / Q000201:enzymology*; D018482:Muscle, Skeletal / Q000201:enzymology* / Q000378:metabolism; D009133:Muscular Atrophy / Q000178:diet therapy / Q000201:enzymology / Q000378:metabolism / Q000517:prevention & control*; D018384:Oxidative Stress
chemical_list: C515029:ALDH2 protein, mouse; D000444:Aldehyde Dehydrogenase; D000071396:Aldehyde Dehydrogenase, Mitochondrial