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Effects of high‐impact exercise on the physical properties of bones of ovariectomized rats fed to a high‐protein diet
Author(s) -
Shimano R. C.,
Yanagihara G. R.,
Macedo A. P.,
Yamanaka J. S.,
Shimano A. C.,
Tavares J. M. R. S.,
Issa J. P. M.
Publication year - 2018
Publication title -
scandinavian journal of medicine and science in sports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.575
H-Index - 115
eISSN - 1600-0838
pISSN - 0905-7188
DOI - 10.1111/sms.13058
Subject(s) - ovariectomized rat , osteocalcin , medicine , osteopontin , endocrinology , bone mineral , immunostaining , jumping , osteoporosis , chemistry , estrogen , alkaline phosphatase , immunohistochemistry , physiology , biochemistry , enzyme
The aim of this study was to evaluate the effects of high‐impact physical exercise as a prophylactic and therapeutic means in osteopenic bones of rats submitted to ovariectomy and protein diet intake. A total of 64 Wistar rats were divided into eight groups (n = 8 each), being: OVX , ovx, standard diet and sedentary; OVXE , ovx, standard diet and jump; OVXP , ovx, high‐protein diet and sedentary; and OVXEP , ovx, high‐protein diet and jump; SH , sham, standard diet and sedentary; SHE , sham, standard diet and jump; SHP , sham, high‐protein diet and sedentary; and SHEP , sham, high‐protein diet and jump. OVX surgery consists of ovariectomy, and sham was the control surgery. The jumping protocol consisted of 20 jumps/day, 5 days/week. The bone structure was evaluated by densitometry, mechanical tests, histomorphometric, and immunohistochemical analyses. A high‐protein diet resulted in increased bone mineral density ( P = .049), but decreased maximal load ( P = .026) and bone volume fraction ( P = .023). The benefits of physical exercise were demonstrated by higher values of the maximal load in the trained groups compared to the sedentary groups ( P < .001). The sham groups had decreased immunostaining of osteocalcin ( P = .004) and osteopontin ( P = .010) compared to ovx groups. However, the high‐protein diet ( P = .005) and jump exercise ( P = .017) resulted in lower immunostaining of osteopontin compared to the standard diet and sedentary groups, respectively. In this experimental model, it was concluded that ovariectomy and a high‐fat diet can negatively affect bone tissue and the high‐impact exercise was not enough to suppress the deleterious effects caused by the protein diet and ovariectomy.