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ARS Home » Southeast Area » Little Rock, Arkansas » Microbiome and Metabolism Research Unit » Research » Publications at this Location » Publication #230738

Title: Short term effects on bone quality associated with consumption of soy protein isolate and other dietary protein sources in rapidly growing female rats

Author
item CHEN, JINRAN - ACNC/UAMS
item SINGHAL, ROHIT - ACNC/UAMS
item LAZARENKO, OXANA - ACNC/UAMS
item LIU, XIAOLI - ACNC/UAMS
item HOGUE, WILLIAM - ACNC/UAMS
item BADGER, THOMAS - ACNC/UAMS
item RONIS, MARTIN - ACNC/UAMS

Submitted to: Experimental Biology and Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/5/2008
Publication Date: 11/10/2008
Citation: Chen, J., Singhal, R., Lazarenko, O.P., Liu, X., Hogue, W.R., Badger, T.M., Ronis, M.J. 2008. Short term effects on bone quality associated with consumption of soy protein isolate and other dietary protein sources in rapidly growing female rats. Experimental Biology and Medicine. 233(11):1348-1358.

Interpretive Summary: The beneficial effects of soy protein consumption on bone quality have been reported, but research on the effects of whey protein hydrolysate and rice protein isolate on bone growth are very limited. The current study compared effects of feeding these three proteins for 14 days on bone mineral density and bone mineral content in healthy intact and ovariectomized rapidly growing female rats relative to animals fed standard casein diet. Whether soy protein isolate has similar effects like sex steroid on bone were also explored. Bone CT scan showed that, in general, all three protein sources had positive effects on either bone mineral density or bone mineral content relative to casein diet, but soy protein isolate had greater effects in both rats populations. These data suggest the beneficial bone effects of a soy diet in rapidly growing animals and the potential for early soy consumption to increase peak bone mass.

Technical Abstract: Beneficial effects of soy protein consumption on bone quality have been reported. The effects of other dietary protein sources such as whey protein hydrolysate (WPH) and rice protein isolate (RPI) on bone growth has been less well examined. The current study compared effects of feeding soy protein isolate (SPI), WPH and RPI for 14 d on tibial bone mineral density (BMD) and bone mineral content (BMC) in intact and ovariectomized (OVX) rapidly growing female rats relative to animals fed casein (CAS). The effects of estrogenic status on responses to SPI were also explored. Tibial peripheral quantitative computerized tomography (pQCT) showed all three protein sources had positive effects on either BMD or BMC relative to CAS (P<0.05), but SPI had greater effects in both intact and OVX female rats. SPI and E2 had positive effects on BMD and BMC in OVX rats (P<0.05). However, trabecular BMD was lower in a SPI+E2 group compared to a CAS+E2 group. In OVX rats, SPI increased serum bone formation markers, and serum from SPI-fed rats stimulated osteoblastogenesis in ex-vivo. SPI also suppressed the bone resorption marker RatLaps (P<0.05). Both SPI and E2 increased alkaline phosphatase gene expression in bone, but only SPI decreased receptor activator of nuclear factor-'B ligand (RANKL) and estrogen receptor gene expression (P<0.05). These data suggest beneficial bone effects of a soy diet in rapidly growing animals and the potential for early soy consumption to increase peak bone mass.