Lycopene Improves Bone Quality and Regulates AGE/RAGE/NF-kB Signaling Pathway in High-Fat Diet-Induced Obese Mice

Objective. This study was aimed at examining the effects of lycopene on bone metabolism in high-fat diet (HFD)- induced obese mice and to identify the potential underlying mechanisms. Methods. Mice were fed a HFD for 12 weeks and then continue with or without lycopene intervention (15 mg/kg) for additional 10 weeks. The effects of lycopene on blood glucose and lipid metabolism, as well as serum levels of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and malondialdehyde (MDA) were determined by biochemical assays. Bone histomorphological features and osteoclast activity were assessed by hematoxylin/eosin and tartrate-resistant acid phosphatase staining. Bone microstructure at the proximal tibial metaphysis and diaphysis was determined by microcomputed tomography. Tibial biomechanical strength and material profiles were measured by a three-point bending assay and Fourier transform infrared spectroscopy. Protein expressions involved in the AGE/RAGE/NF-kB signaling pathway were determined by western blot and/or immunohistochemical staining. Results. Lycopene consumption reduced body weight gain and improved blood glucose and lipid metabolism in HFD-induced obese mice. In addition, lycopene treatment preserved bone biomechanical strength, material profiles, and microarchitecture in obese mice. Moreover, these alterations were associated with an increase in serum levels of T-AOC and SOD, and a decline in serum levels of MDA, as well as a reduction of AGEs, RAGE, cathepsin K, and p-NF-kBp65 and NF-kBp65 expressions in the femurs and tibias of obese mice. Conclusion. Lycopene may improve bone quality through its antioxidant properties, which may be linked with the regulation of the AGE/RAGE/NF-kB signaling pathway in obese mice. These results suggest that lycopene consumption may be beneficial for the management of obesity-induced osteoporosis.