Effects of diet-induced obesity and voluntary wheel running on the microstructure of the murine distal femur.
BACKGROUND
Obesity and osteoporosis, two possibly related conditions, are rapidly expanding health concerns in modern society. Both of them are associated with sedentary life style and nutrition. To investigate the effects of diet-induced obesity and voluntary physical activity we used high resolution micro-computed tomography (μCT) together with peripheral quantitative computed tomography (pQCT) to examine the microstructure of the distal femoral metaphysis in mice.


METHODS
Forty 7-week-old male C57BL/6J mice were assigned to 4 groups: control (C), control + running (CR), high-fat diet (HF), and high-fat diet + running (HFR). After a 21-week intervention, all the mice were sacrificed and the left femur dissected for pQCT and μCT measurements.


RESULTS
The mice fed the high-fat diet showed a significant weight gain (over 70% for HF and 60% for HFR), with increased epididymal fat pad mass and impaired insulin sensitivity. These obese mice had significantly higher trabecular connectivity density, volume, number, thickness, area and mass, and smaller trabecular separation. At the whole bone level, they had larger bone circumference and cross-sectional area and higher density-weighted maximal, minimal, and polar moments of inertia. Voluntary wheel running decreased all the cortical bone parameters, but increased the trabecular mineral density, and decreased the pattern factor and structure model index towards a more plate-like structure.


CONCLUSIONS
The results suggest that in mice the femur adapts to obesity by improving bone strength both at the whole bone and micro-structural level. Adaptation to running exercise manifests itself in increased trabecular density and improved 3D structure, but in a limited overall bone growth.
Department of Health Sciences, University of Jyväskylä, Finland. harri.k.suominen@jyu.fi.
Hongqiang
H
Ma
Tuomas
T
Turpeinen
Mika
M
Silvennoinen
Sira
S
Torvinen
Rita
R
Rinnankoski-Tuikka
Heikki
H
Kainulainen
Jussi
J
Timonen
Urho M
UM
Kujala
Paavo
P
Rahkila
Harri
H
Suominen
J Altern Complement Med. 2009 Apr;15(4):415-21
19388864
Best Pract Res Clin Endocrinol Metab. 2005 Dec;19(4):525-46
16311215
Pediatr Res. 2007 Oct;62(4):462-7
17667858
J Bone Joint Surg Br. 2002 Aug;84(6):900-7
12211688
J Clin Endocrinol Metab. 2008 Jun;93(6):2181-7
18364384
Calcif Tissue Int. 2007 Oct;81(4):285-93
17828460
J Cell Biochem. 2006 Oct 15;99(3):824-34
16721825
J Nutr. 2000 Sep;130(9):2274-84
10958824
J Bone Miner Res. 2008 Jan;23(1):17-29
17784844
Obes Rev. 2008 Mar;9 Suppl 1:48-52
18307699
J Strength Cond Res. 2005 Aug;19(3):667-72
16095423
J Bone Miner Res. 2009 Aug;24(8):1427-33
19335223
Am J Physiol Regul Integr Comp Physiol. 2007 Nov;293(5):R2015-26
17881616
J Bone Miner Metab. 2008;26(3):226-30
18470662
Metabolism. 2011 Mar;60(3):373-88
20359721
J Bone Miner Res. 2003 Nov;18(11):2002-9
14606513
Proc Natl Acad Sci U S A. 2004 Mar 2;101(9):3258-63
14978271
J Clin Endocrinol Metab. 2008 Jan;93(1):110-7
17956951
Osteoporos Int. 2008 Jul;19(7):905-12
17924050
Bone. 1996 May;18(5):397-403
8739896
Bone. 2009 Jun;44(6):1097-104
19264159
J Cell Biochem. 2006 May 15;98(2):251-66
16479589
Bone. 2007 Dec;41(6):995-1004
17888748
J Electron Microsc (Tokyo). 2003;52(6):503-13
14756238
Genet Res (Camb). 2008 Oct;90(5):433-44
19061533
Am J Clin Nutr. 2004 Aug;80(2):514-23
15277178
J Bone Miner Res. 1999 Jul;14(7):1167-74
10404017
Med Sport Sci. 2007;51:33-49
17505118
Obes Surg. 2008 Sep;18(9):1134-43
18563500
J Geriatr Phys Ther. 2005;28(3):102-7
16386172
Osteoporos Int. 2008 May;19(5):595-606
17965817
Calcif Tissue Int. 2004 May;74(5):469-75
14961209
Metabolism. 2006 Dec;55(12):1616-8
17142133
Am J Clin Nutr. 2007 Nov;86(5):1530-8
17991669
Bone. 2010 Jan;46(1):217-25
19853069
Int J Obes (Lond). 2005 Nov;29(11):1368-78
16088331
J Pediatr (Rio J). 2005 Jul-Aug;81(4):337-42
16106320
J Women Aging. 2008;20(3-4):297-308
18983113
J Nutr. 2009 Mar;139(3):502-6
19176752
Med Sci Sports Exerc. 1999 Nov;31(11 Suppl):S534-41
10593524
J Appl Physiol (1985). 1994 May;76(5):1999-2005
8063662
Obesity (Silver Spring). 2007 Nov;15(11):2605-13
18070751
J Nutr. 2006 Jan;136(1):159-65
16365076
Curr Opin Clin Nutr Metab Care. 2002 Sep;5(5):525-31
12172476
Bone. 2007 Apr;40(4):1120-7
17240210
J Mol Endocrinol. 2009 Jul;43(1):11-8
19240195
J Appl Physiol (1985). 2004 Sep;97(3):806-10
15090485
J Morphol. 2008 Mar;269(3):313-8
17957711
Bone. 2007 Oct;41(4):505-15
17693147
J Bone Miner Res. 2010 Jun;25(6):1423-32
19874197
Clin Exp Pharmacol Physiol. 2003 Oct;30(10):769-78
14516417
J Musculoskelet Neuronal Interact. 2006 Jul-Sep;6(3):258-63
17142947
Nat Clin Pract Rheumatol. 2006 Jan;2(1):35-43
16932650
J Bone Miner Res. 2002 Jun;17(6):1044-50
12054159
Calcif Tissue Int. 2010 May;86(5):411-9
20229059
Bone. 2009 Mar;44(3):404-12
19095090
J Bone Miner Res. 2009 Jan;24(1):50-61
18715135
Bone. 2008 Apr;42(4):660-8
18291744
Bone. 2008 Sep;43(3):521-31
18602880
J Musculoskelet Neuronal Interact. 2000 Sep;1(1):25-30
15758521
Obesity (Silver Spring). 2007 Aug;15(8):1996-2005
17712117
J Bone Miner Res. 2004 Oct;19(10):1640-50
15355559
J Bone Miner Res. 2001 Jan;16(1):182-8
11149483
J Appl Physiol (1985). 2002 Sep;93(3):887-93
12183482
J Clin Invest. 2003 Dec;112(12):1796-808
14679176
Am J Physiol Endocrinol Metab. 2006 Feb;290(2):E258-67
16403782
Clin Biomech (Bristol, Avon). 2006 Mar;21(3):235-44
16356612
Technol Health Care. 1998 Dec;6(5-6):351-9
10100938