Resveratrol supplementation preserves long bone mass, microstructure, and strength in hindlimb-suspended old male rats.

Resveratrol has gained popularity as an "anti-aging" compound due to its antioxidant and anti-inflammatory properties. Few studies have investigated the role of resveratrol supplementation in the prevention of age-related bone loss and skeletal disuse despite increased inactivity and age-related bone loss in the elderly. The objective of the study was to investigate the effect of resveratrol supplementation on disuse and age-related bone loss. Old (age 33 months) Fischer 344 × Brown Norway male rats were provided either trans-resveratrol (12.5 mg/kg bw/day) or deionized distilled water by oral gavage for 21 days. Rats were hindlimb-suspended (HLS) or kept ambulatory (AMB) for 14 days. Both femora and tibiae were collected. Bone mass was measured by dual-energy X-ray absorptiometry and bone microstructure was determined by micro-computed tomography. HLS of old male rats accelerated loss of bone mineral content, decreased trabecular bone volume per unit of total volume, and increased trabecular separation. Resveratrol supplementation ameliorated bone demineralization and loss of bone microarchitecture in HLS old male rats. The peak force measured by the three-point bending test was reduced (P = 0.007) in HLS/control compared to AMB/control rats. Resveratrol supplementation ameliorated HLS-induced loss of femur strength. Plasma osteocalcin and alkaline phosphatase was higher (P < 0.04) and C-reactive protein was lower (P = 0.04) in old male rats given resveratrol. The bone protective effects of resveratrol appeared to be mediated through increased osteoblast bone formation, possibly due to reduced inflammation. Based on the results, resveratrol supplementation appeared to provide a feasible dietary therapy for preserving the skeletal system during disuse and age-related bone loss.

Resveratrol supplementation influences bone properties in the tibia of hindlimb-suspended mature Fisher 344 × Brown Norway male rats.

The deleterious bone effects of mechanical unloading have been suggested to be due to oxidative stress and (or) inflammation. Resveratrol has both antioxidant and anti-inflammatory properties; therefore, the study's objective was to determine whether providing resveratrol in the low supplementation range for a short duration prevents bone loss during mechanical unloading. Mature (6 months old) Fischer 344 × Brown Norway male rats were hindlimb-suspended (HLS) or kept ambulatory for 14 days. Rats were provided either trans-resveratrol (RES; 12.5 mg/kg body mass per day) or deionized distilled water by oral gavage for 21 days (7 days prior to and during the 14 days of HLS). Bone mass was measured by dual energy X-ray absorptiometry. Bone microstructure was determined by microcomputed tomography. HLS of rats resulted in femur trabecular bone deterioration. Resveratrol supplementation did not attenuate trabecular bone deterioration in HLS rats. Unexpectedly, HLS-RES rats had the lowest tibial bone mineral content (P < 0.05), calcium content and lower cortical thickness (P < 0.05), and increased porosity compared with HLS/control rats. Plasma osteocalcin was also lower (P < 0.04) in HLS/resveratrol rats. There were no significant effects on plasma C-reactive protein, a marker of systemic inflammation, or total antioxidant capacity. However, HLS-RES rats showed a negative relationship (r(2) = 0.69, P = 0.02) between plasma osteocalcin and thiobarbituric acid reactive substances, a marker of lipid peroxidation. Based on the results, resveratrol supplementation of 6-month-old HLS male rats had no bone protective effects and possibly even detrimental bone effects.