title: Short-term caloric restriction does not reduce bone mineral density in rats with early type 2 diabetes.
abstract: BACKGROUND
  The effect of caloric restriction (CR) in the setting of diabetes on bone metabolism has not yet been fully studied. The aim of this study is to determine if short-term CR alters bone mass and metabolism in Otsuka Long-Evans Tokushima fatty (OLETF) rats, an animal model of type 2 diabetes.
  
  
  METHODS
  Four groups (n=5) were created: OLETF rats with food ad libitum (AL), OLETF rats with CR, Long-Evans Tokusima Otsuka (LETO) rats with food AL, and LETO rats with CR. The CR condition was imposed on 24-week-old male rats using a 40% calorie reduction for 4 weeks. The effect of CR on femoral bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry. Serum markers were measured by immunoassay.
  
  
  RESULTS
  After 4 weeks of CR, body weight decreased in both strains. The BMD decreased in LETO rats and was maintained in OLETF rats. After adjustment for body weight, BMD remained lower in LETO rats (P=0.017) but not OLETF rats (P=0.410). Bone-specific alkaline phosphatase levels decreased in LETO rats (P=0.025) but not in OLEFT rats (P=0.347). Serum leptin levels were reduced after CR in both strains, but hyperleptinemia remained in OLETF rats (P=0.009). CR increased 25-hydroxyvitamin D levels in OLETF rats (P=0.009) but not in LETO rats (P=0.117). Additionally, interleukin-6 and tumor necrosis factor-α levels decreased only in OLETF rats (P=0.009).
  
  
  CONCLUSIONS
  Short-term CR and related weight loss were associated with decreases of femoral BMD in LETO rats while BMD was maintained in OLETF rats. Short-term CR may not alter bone mass and metabolism in type 2 diabetic rats.
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea. ; Medical Research Institute, Pusan National University School of Medicine, Busan, Korea.
authors.forename: Yun Kyung
authors.initials: YK
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea. ; Medical Research Institute, Pusan National University School of Medicine, Busan, Korea.
authors.forename: Won Jin
authors.initials: WJ
authors.lastname: Kim
authors.affiliation: Medical Research Institute, Pusan National University School of Medicine, Busan, Korea. ; Department of Rehabilitation Medicine, Pusan National University School of Medicine, Busan, Korea.
authors.forename: Myung Jun
authors.initials: MJ
authors.lastname: Shin
authors.affiliation: Pusan National University Collegy of Pharmacy, Busan, Korea.
authors.forename: Hae-Young
authors.initials: HY
authors.lastname: Chung
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea. ; Medical Research Institute, Pusan National University School of Medicine, Busan, Korea.
authors.forename: Sang Soo
authors.initials: SS
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea. ; Medical Research Institute, Pusan National University School of Medicine, Busan, Korea.
authors.forename: Bo Hyun
authors.initials: BH
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Pusan National University School of Medicine, Busan, Korea.
authors.forename: Seong-Jang
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Kim Yong Ki Internal Medicine Clinic, Busan, Korea.
authors.forename: Yong Ki
authors.initials: YK
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea. ; Medical Research Institute, Pusan National University School of Medicine, Busan, Korea.
authors.forename: In Joo
authors.initials: IJ
authors.lastname: Kim
keywords: Bone density; Caloric restriction; Diabetes mellitus, type 2
references.citation: Cytokine. 2002 Jun 21;18(6):334-9
references.pmid: 12160522
references.citation: J Bone Miner Metab. 2008;26(6):618-23
references.pmid: 18979162
references.citation: J Bone Miner Res. 1989 Feb;4(1):97-101
references.pmid: 2718784
references.citation: J Clin Endocrinol Metab. 2002 Mar;87(3):1030-5
references.pmid: 11889157
references.citation: J Nutr Sci Vitaminol (Tokyo). 1991 Dec;37 Suppl:S43-9
references.pmid: 1820443
references.citation: PLoS One. 2013 Jul 02;8(7):e68497
references.pmid: 23844209
references.citation: Endocrinology. 2008 Feb;149(2):634-41
references.pmid: 17991723
references.citation: Exp Cell Res. 2005 Sep 10;309(1):99-109
references.pmid: 15963981
references.citation: J Bone Miner Res. 2012 Jun;27(6):1390-6
references.pmid: 22407876
references.citation: J Bone Miner Res. 2008 Jun;23(6):870-8
references.pmid: 18435579
references.citation: J Clin Endocrinol Metab. 2004 Mar;89(3):1196-9
references.pmid: 15001609
references.citation: J Clin Endocrinol Metab. 2001 Jan;86(1):32-8
references.pmid: 11231974
references.citation: Bone. 1988;9(1):29-36
references.pmid: 3259888
references.citation: Osteoporos Int. 2001;12(8):688-98
references.pmid: 11580083
references.citation: J Leukoc Biol. 2008 Oct;84(4):882-92
references.pmid: 18579754
references.citation: N Engl J Med. 2004 Sep 2;351(10):987-97
references.pmid: 15342807
references.citation: J Nutr. 2010 Jan;140(1):31-7
references.pmid: 19923391
references.citation: Clin Endocrinol (Oxf). 2009 Feb;70(2):214-20
references.pmid: 18547340
references.citation: Nature. 1996 Jul 18;382(6588):250-2
references.pmid: 8717038
references.citation: J Clin Invest. 1985 Jul;76(1):370-3
references.pmid: 2991340
references.citation: Osteoporos Int. 2005 Oct;16(10):1263-71
references.pmid: 15702263
references.citation: Metabolism. 1985 Sep;34(9):797-801
references.pmid: 4033421
references.citation: Bone. 1993;14(1):29-33
references.pmid: 8442999
references.citation: Ann Intern Med. 1993 May 1;118(9):657-65
references.pmid: 8460853
references.citation: Diabetes. 1992 Nov;41(11):1422-8
references.pmid: 1397718
references.citation: Scand J Rheumatol Suppl. 1996;103:65-74
references.pmid: 8966493
references.citation: Osteoporos Int. 2001;12(3):199-206
references.pmid: 11315238
references.citation: J Diabetes Complications. 1996 Jul-Aug;10(4):201-5
references.pmid: 8835919
references.citation: Exp Gerontol. 2009 Jan-Feb;44(1-2):41-5
references.pmid: 18502597
references.citation: Ann Intern Med. 1995 Mar 15;122(6):409-14
references.pmid: 7856988
references.citation: Diabetes Care. 2003 Jan;26 Suppl 1:S5-20
references.pmid: 12502614
references.citation: Biochem Biophys Res Commun. 2005 Jun 3;331(2):520-6
references.pmid: 15850790
references.citation: Clin Endocrinol (Oxf). 2001 Sep;55(3):341-7
references.pmid: 11589677
references.citation: J Bone Miner Metab. 2009;27(5):613-9
references.pmid: 19466592
references.citation: N Engl J Med. 1976 Jan 29;294(5):241-5
references.pmid: 1244549
references.citation: J Gerontol A Biol Sci Med Sci. 1999 Nov;54(11):B478-91
references.pmid: 10619311
references.citation: Biochem Biophys Res Commun. 2002 Jul 12;295(2):475-81
references.pmid: 12150974
references.citation: Calcif Tissue Int. 1998 Dec;63(6):456-8
references.pmid: 9817937
references.citation: Osteoporos Int. 1999;10(4):307-11
references.pmid: 10692980
references.citation: J Clin Endocrinol Metab. 2001 May;86(5):1884-7
references.pmid: 11344177