Bone mineral density (BMD) in rats in a model of metabolic syndrome (metS)

Abstract

Background/Aims: Studies assessing association between MetS and bone status have yielded inconsistent results; subjects with MetS had lower bone mineral density (BMD) but also lower fracture risk. We investigated BMD in an animal model of MetS and the effects of feeding a variety of different nutraceuticals. Methods: Male Wistar rats were fed on either a corn starch (CS) or highcarbohydrate, high-fat (HCHF) diet that produces physiological characteristics of MetS for 8 weeks followed by a further 8 weeks during which half of each group of rats received a dietary supplement of a nutraceutical (including cardamom, chia, inulin, lignan, linseed oil, caffeine, seaweeds; n ¼ 8-15 per group, n ¼ 194 control diet). BMD of rats was determined at 16 weeks using dual energy x-ray absorptiometry (Norland XR36). Difference between groups was tested using two-way ANOVA; factors, diet and nutraceutical. Results:Rats fed the HCHF diet were significantly heavier than those fed on the CS diet (474.5 ± 4.3 vs. 401.7 ± 4.3 g, p < 0.0001 respectively) but control HCHF rats had significantly lower (p<0.0001)%BMD than CS-fed rats (0.035±0.0002 vs. 0.041 ± 0.0002% respectively). Caffeine (p < 0.001), lignan (p ¼ 0.005) and seaweeds (p < 0.001) significantly decreased BMD while feeding lignan (p ¼ 0.005) and linseed oil (p¼0.038) increased BMD relative to controls. Inulin (p< 0.001) and chokeberry (p ¼ 0.0015) significantly increased %BMD. Conclusions: An HCHF (MetS) diet increased overall BMD due to a larger body mass but decreased BMD relative to body weight; partly offset by supplementation with chia seeds, chokeberry or inulin.